• 专利附录
  • 专利说明
  • 权利要求
  • 类似技术
  • 同族专利
  • 引用文献
  • 法律状态
  • 优先权
    • 专利摘要:
    The transparent electrode is formed on the glass substrate, and the amorphous silicon layer is formed on the transparent electrode. As the metal catalyst element, a nickel layer is formed on the surface of the amorphous silicon layer and brought into contact with the surface thereof, and the amorphous silicon layer is crystallized by heat treatment to form a p-type polycrystalline silicon layer. This polycrystalline silicon layer is crystallographically oriented and has high crystallinity. The polycrystalline silicon layer is used to form a p-type polycrystalline silicon layer having high crystallinity while being crystallographically oriented as seed crystals. In addition, an i-type polycrystalline silicon layer and an n-type polycrystalline silicon layer are successively formed on the polycrystalline silicon layer. With the above configuration, it is possible to provide a method for manufacturing a crystalline silicon thin film semiconductor device, a crystalline silicon thin film photovoltaic device and a crystalline silicon thin film semiconductor device capable of realizing high crystallinity, crystal orientation, high characteristics and excellent productivity of polycrystalline silicon. .
    公开号:KR20030017202A
    申请号:KR1020010051387
    申请日:2001-08-24
    公开日:2003-03-03
    发明作者:오카후미히토；무라마쓰신이치；미나가와야스시
    申请人:히다찌 케이블 리미티드；
    IPC主号:
    专利说明:

    Crystalline thin film semiconductor device, crystalline silicon thin film photovoltaic device and method for manufacturing a crystalline silicon thin film semiconductor device
    [12] The present invention relates to a method for manufacturing a crystalline silicon thin film semiconductor device, a crystalline silicon thin film photovoltaic device, and a crystalline silicon thin film semiconductor device, and in particular, a crystalline silicon thin film in which a polycrystalline silicon thin film is formed by using amorphous silicon as a seed crystal. A semiconductor device, a crystalline silicon thin film photovoltaic device, and a method for manufacturing a crystalline silicon thin film semiconductor device.
    [13] In a semiconductor device such as a solar cell, in order to form a high quality crystalline silicon device having a thickness of about 1 to 4 µm on a glass substrate having a conductive film (layer) thereon, the high quality seed crystal is formed on a glass substrate having a conductive film thereon. It must be formed directly. The requirement to be satisfied in the formation of this seed crystal is
    [14] (1) high crystallinity (high crystallinity),
    [15] (2) crystallographic orientation,
    [16] (3) one mass throughput,
    [17] (4) It includes a low temperature process using a general glass substrate.
    [18] In the manufacture of solar cells, the manufacturing method of forming a polycrystalline silicon thin film on dissimilar substrates, such as glass, has been employ | adopted until now. According to this manufacturing method, it is not necessary to use a large area and a high quality silicon crystal substrate, and a considerable reduction in cost can be expected. However, in the manufacture of semiconductor devices having good characteristics, the quality of the polycrystalline silicon thin film must be improved. To this end, generally, quartz or the like that can withstand high temperatures is used as a substrate, and the substrate is easily subjected to high temperature deposition to form a silicon thin film having good crystallinity. However, in this manufacturing method, since expensive substrates such as quartz are used, the cost cannot be reduced.
    [19] To solve this problem, a method is proposed in K. Yamomoto et al., IEEE "First World Conference on Photovoltaic Energy Conversion," 1575-1578 (1994). According to this method, this amorphous thin film silicon is melted and crystallized by laser annealing, for example, to form a film on the surface of the substrate, thereby producing polycrystalline thin film silicon having good crystallinity. This method has an advantage in that a low cost substrate material can be used because the temperature rise of the substrate can be suppressed. In addition, for example, there have been attempts to form polycrystalline silicon directly on a glass substrate having a conductive film thereon by plasma CVD (Plasma Chemical Vapor Deposition).
    [20] Another method for solving the above problem is proposed in Japanese Patent Laid-Open No. 82997/1997. According to this method, amorphous silicon is crystallized by a metal catalyst, and has the same p- or n-conducting type as all crystal layers of the same p- or n-conducting type or BSF (back surface field). All crystal layers are crystallized.
    [21] However, according to the conventional crystalline silicon thin film semiconductor device and the crystalline silicon thin film photovoltaic device, when amorphous silicon is crystallized on a glass substrate by laser heat treatment, many substrates cannot be processed simultaneously without difficulty. This causes a problem of throughput. In particular, in order to convert the amorphous thin film silicon into a polycrystalline layer having a uniform grain diameter by dissolution crystallization, the amorphous thin film silicon is formed by plasma CVD, and the hydrogen contained in the amorphous thin film silicon is thermally removed. However, the method of performing laser heat treatment should be used. Thus, product manufacture involves many problems and a lot of time that increases costs.
    [22] On the other hand, a manufacturing method of directly forming polycrystalline silicon on a glass substrate or the like by plasma CVD has problems in quality such as low crystallinity of the resulting polycrystalline silicon. In general, in the pn structure and the pin structure adopted in the solar cell, a p-conductive or n-conductive polycrystalline silicon thin film is formed directly on a glass substrate having a conductive film on its surface. However, polycrystalline silicon thin films formed directly on a glass substrate by plasma CVD are known to have problems such as low crystallinity and short operating life. In particular, p-conducting polycrystalline silicon thin films formed by plasma CVD contain very low crystallinity and insufficient crystal orientation, which have serious technical problems.
    [23] In addition, according to the method disclosed in Japanese Patent Laid-Open No. 82997/1997, there is a possibility that nickel silicide (silicon alloy with nickel) is left in the joint portion with another conductive type. Also, even when the remaining nickel silicide is removed by etching, there is a possibility that a defect occurs. Thus, recombination at the junction increases. For this reason, there exists a possibility that the characteristic of a solar cell apparatus may fall very much.
    [24] Accordingly, an object of the present invention is to provide a crystalline silicon thin film semiconductor device, a crystalline silicon thin film photovoltaic device and a crystalline silicon thin film semiconductor device manufacturing method capable of realizing high crystallinity, excellent crystal orientation, high characteristics and high productivity of polycrystalline silicon. It is.
    [1] 1 is a schematic cross-sectional view showing an intermediate step in the manufacture of a solar cell according to a first embodiment of the present invention,
    [2] FIG. 2 is a schematic cross-sectional view showing a completed state of the solar cell shown in FIG. 1;
    [3] 3 is a schematic cross-sectional view showing an intermediate step in the manufacture of a solar cell according to a second embodiment of the present invention;
    [4] 4 is a schematic cross-sectional view showing a completion state of the solar cell shown in FIG. 3;
    [5] 5 is a schematic cross-sectional view showing an intermediate step in the manufacture of a solar cell according to a fourth embodiment of the present invention;
    [6] 6 is a schematic cross-sectional view showing a solar cell according to a fifth embodiment of the present invention.
    [7] * Description of the symbols for the main parts of the drawings *
    [8] 1 glass substrate 2 transparent electrode
    [9] 3: amorphous silicon layer 3A, 5: p-type polycrystalline silicon layer
    [10] 4: nickel layer 6: i-type polycrystalline silicon layer
    [11] 7: n-type polycrystalline silicon layer 8: aluminum layer
    [25] According to the first aspect of the present invention, a crystalline silicon thin film semiconductor device,
    [26] A conductive substrate or a substrate having a conductive layer on its surface,
    [27] A crystalline phase formed by introducing a metal catalyst element into an amorphous silicon layer formed on the surface of the conductive substrate or the conductive layer and contacting the surface portion of the amorphous silicon layer, and heat treating the amorphous silicon layer to crystallize the amorphous silicon layer A first polycrystalline silicon layer oriented with
    [28] The first polycrystalline silicon layer is used as a seed crystal to include a second polycrystalline silicon layer formed to have the same conductivity type as the first polycrystalline silicon layer.
    [29] According to this configuration, the metal catalyst element is introduced into the amorphous silicon layer formed on the substrate, that is, brought into contact with the amorphous silicon layer, and crystallographically oriented the amorphous silicon layer through the action of the metal catalyst element at low temperature by heat treatment. To the first polycrystalline silicon layer. When this first silicon layer is used as seed crystals to form a second polycrystalline silicon layer on the surface of the first silicon layer, the resulting second polycrystalline silicon layer has the same crystal orientation as the first polycrystalline silicon layer as the substrate. Has high crystallinity Similarly, the third polycrystalline silicon layer formed by using the second polycrystalline silicon layer as a substrate has a high crystallinity and is crystallographically oriented. As a result, a crystalline silicon thin film semiconductor device capable of realizing high crystallinity, excellent crystal orientation, high characteristics and high productivity can be manufactured. In addition, silicide does not remain in the junction part which has another conductivity type. Thus, there is no need to provide a process for removing the silicide, and no defect due to the silicide occurs.
    [30] According to a second aspect of the present invention, a crystalline silicon thin film photovoltaic device is,
    [31] An insulating substrate having a conductive layer on the conductive substrate or surface;
    [32] A first catalyst formed by introducing a metal catalyst element into an amorphous silicon layer formed on the surface of the conductive substrate or the conductive layer to be brought into contact with the surface portion of the amorphous silicon layer, and heat treating the amorphous silicon layer to crystallize the amorphous silicon layer A first polycrystalline silicon layer of conductive type,
    [33] A second polycrystalline silicon layer formed to have the same conductivity type as the first conductivity type using the first polycrystalline silicon layer as a seed crystal;
    [34] An i-type third polycrystalline silicon layer substantially formed on the second polycrystalline silicon layer;
    [35] A fourth polycrystalline silicon layer formed on the third polycrystalline silicon layer and of a second conductivity type different from the first conductivity type,
    [36] An electrode portion formed on the fourth polycrystalline silicon layer.
    [37] According to a third aspect of the present invention, a crystalline silicon thin film photovoltaic device is,
    [38] An insulating substrate having electrodes on its surface,
    [39] A metal catalyst element was introduced into the amorphous silicon layer formed on the electrode of the insulating substrate to be brought into contact with the surface portion of the amorphous silicon layer, and the amorphous silicon layer was heat treated to crystallize the amorphous silicon layer to form the first conductivity type. A first polycrystalline silicon layer,
    [40] A second polycrystalline silicon layer formed to have the same conductivity type as the first conductivity type using the first polycrystalline silicon layer as a seed crystal;
    [41] A third polycrystalline silicon layer formed on the second polycrystalline silicon layer and being of a second conductivity type different from the first conductivity type,
    [42] An electrode portion formed on the third polycrystalline silicon layer.
    [43] In the configuration of the second and third features of the present invention, the metal catalyst element is introduced into the amorphous silicon layer formed on the substrate and brought into contact with the amorphous silicon layer, and through the action of the metal catalyst element at low temperature by heat treatment, the amorphous The silicon layer is converted to a crystallographically oriented first polycrystalline silicon layer. When this first silicon layer is used as seed crystal to form a second polycrystalline silicon layer on the surface of the first silicon layer, the resulting second polycrystalline silicon layer is the same crystal orientation as the first polycrystalline silicon layer as the substrate. Has high crystallinity Similarly, the third polycrystalline silicon layer formed using the second polycrystalline silicon layer as a substrate has high crystallinity and is crystallographically oriented. Therefore, the crystalline silicon thin film photovoltaic device can be manufactured to realize high crystallinity, crystal orientation, high characteristics and excellent productivity.
    [44] According to a fourth aspect of the present invention, a method of manufacturing a crystalline silicon thin film semiconductor device is
    [45] Preparing a substrate having a conductive layer on the conductive substrate or surface and forming an amorphous silicon thin film on the surface of the conductive substrate or on the surface of the conductive layer of the substrate,
    [46] Introducing a metal catalyst element into the amorphous silicon layer to be in contact with the surface portion of the amorphous silicon layer, and heat treating the amorphous silicon layer to crystallize the amorphous silicon layer and form a crystallographically oriented first polycrystalline silicon layer; ,
    [47] Forming a second polycrystalline silicon layer having the same conductivity type as the first polycrystalline silicon layer using the first polycrystalline silicon layer as seed crystals on the first polycrystalline silicon layer;
    [48] Forming a third polycrystalline silicon layer on the second polycrystalline silicon layer, the third polycrystalline silicon layer having a second conductivity type different from the conductivity type of the second polycrystalline silicon layer.
    [49] According to this manufacturing method, an amorphous silicon thin film is formed on the surface of the substrate, the metal catalyst element is introduced into the amorphous silicon layer and brought into contact with the surface portion of the amorphous silicon layer, and the amorphous silicon layer is heat treated. This makes it possible to crystallize the amorphous silicon layer at low temperatures and form a first polycrystalline silicon layer that is crystallographically oriented. When the first polycrystalline silicon layer is used as seed crystal to form a second polycrystalline silicon layer having the same conductivity type as the first polycrystalline silicon layer on the first polycrystalline silicon layer, the second polycrystalline silicon layer is the first polycrystalline silicon. It has the same crystal orientation as the layer. In addition, a third polycrystalline silicon layer having a conductivity type different from that of the second polycrystalline silicon layer is formed on the second polycrystalline silicon layer to form a semiconductor device having a pn structure. Therefore, the crystalline silicon thin film semiconductor device can be manufactured so that high crystallinity, crystal orientation, high characteristics and excellent productivity can be realized.
    [50] Hereinafter, preferred embodiments of the present invention will be described.
    [51] (First embodiment)
    [52] 1 and 2 show a first embodiment of a crystalline silicon thin film semiconductor device (a crystalline silicon thin film photovoltaic device, that is, a fin type solar cell) according to the present invention. 1 shows an intermediate step in the first embodiment of the present invention. FIG. 2 illustrates a completion state of the crystalline silicon thin film semiconductor device illustrated in FIG. 1. The semiconductor device according to this embodiment includes a substrate including a glass substrate and formed on one side of the glass substrate, a transparent electrode mainly made of tin oxide, and a solar cell formed on the transparent electrode.
    [53] As shown in FIG. 1, the substrate comprises an 800 nm thick transparent electrode 2 formed on the glass substrate 1 at its major surface. SnO 2 was used as the transparent electrode 2, and the concave and the convex portions were formed on the surface of the transparent electrode 2 (in Fig. 1, the concave and convex portions are not shown). The 20 nm-thick p-type impurity-containing amorphous silicon layer 3 has a mixed gas composed of H 2 , SiH 4 (silane) and B 2 H 6 (diborane) at a frequency of 60 MHz, on the surface of the transparent electrode 2. It was introduced into a phase and formed by p-CVD (plasma CVD) under the condition that the pressure was maintained at 0.5 torr and the substrate temperature was 420 ° C. The thickness of the amorphous silicon layer 3 was 50 nm or less, and it is preferable that it is as small as possible. This is because, when crystallized using a metal catalyst element, the amorphous silicon layer 3 is used as seed crystal.
    [54] Next, as a metal catalyst element, a 1 nm thick nickel layer 4 is formed by vacuum deposition, and heat treated in a nitrogen atmosphere at a temperature of 450 to 700 ° C. (particularly a temperature range of 500 to 600 ° C.). (Nickel) was diffused. The heat treatment at this time is not limited to the treatment of nitrogen atmosphere, and the crystallization effect obtained by the heat treatment of nitrogen atmosphere was obtained by heat treatment of vacuum atmosphere, hydrogen atmosphere, argon atmosphere or halide atmosphere.
    [55] In addition, heat treatment was performed in two steps. First, the heat treatment was performed in a hydrogen atmosphere of 400 ° C. so that the hydrogen content of the amorphous silicon layer 3 was 1% or less, preferably 0.3% or less. Next, heat treatment was performed at 550 ° C. As a result, a high crystallographically oriented p-type polycrystalline silicon layer 3A (shown in FIG. 2) was formed. The crystal orientation of this polycrystalline silicon layer 3A was (110). In the above-described process, first, the amorphous silicon layer 3 is formed on the glass substrate 1, and the metal catalyst element is introduced. In addition, a process in which a metal catalyst layer (nickel layer 4) is first deposited directly on the glass substrate 1 and an amorphous silicon layer 3 is formed may be adopted.
    [56] In addition, nickel, iron, cobalt, platinum, copper, gold, or the like may be used as the metal catalyst element. The method of forming the metal catalyst layer may be performed in the formation of the metal catalyst layer in the form of a film, by plasma treatment, vacuum deposition, rotary coating, or the like, in the formation of the metal catalyst layer in a linear or island form. Vacuum deposition in a state covered with a metal mask.
    [57] In addition, methods that can be introduced into the layer include, for example, ion implantation and plasma doping. Since the metal catalyst layer is used for catalytic effect purposes, the concentration of the urea may be very low. In general, the metal catalyst layer is a multi-layered structure of two or three layers with a total thickness of several angstroms. However, the metal catalyst layer may have a single layer structure as long as the catalyst metal proceeds through the reaction through the surface layer to be crystallized, and when the catalyst metal reaches the opposite side, the entire surface layer is in a crystallized state. If the quality of the seed crystal is not critical, crystallization may be carried out under conditions such that the catalytic metal remains in the layer.
    [58] In the heat treatment, the metal catalyst element diffuses into the amorphous silicon layer 3 and precipitates in the circumferential portion between the amorphous silicon layer 3 and the transparent electrode layer 2 on the side distant from the metal catalyst layer (ie, the metal catalyst). The urea moves to the outermost surface of the p-type polycrystalline silicon layer 3A), only the trace amount of the metal catalyst element remains in the polycrystalline silicon layer 3A. Thus, a high quality p-type polycrystalline silicon layer 3A can be formed. If the crystallinity is bad, nickel atoms remain in the layer. However, only 2% or less of the thickness of the entire solar cell device is only considered by the seed crystal portion, and the remaining nickel atoms in the layer do not significantly affect the performance of the solar cell device.
    [59] Therefore, even if the thickness of the polycrystalline silicon layer 3A having nickel-containing seed crystals is 5 nm or less, the quality thereof is not deteriorated, and a high-quality device in which the main portion due to power generation does not contain nickel can be manufactured. In addition, at junctions that are important in solar cell devices, when the different crystal layers in the conductive type are in contact with each other, there is no damage of the residual metal catalyst, for example, due to the etching of the position. Therefore, it is possible to form an ideal joint.
    [60] Next, the 40-nm-thick p-conductive polycrystalline silicon layer 5 has a mixed gas composed of B 2 H 6 , H 2, and SiH 4 , a pressure of 0.5 torr, and a substrate temperature of 200 ° C. Under 60 MHz-p-CVD. Thereafter, the i-type polycrystalline silicon layer 6 was formed by 60 MHz-p-CVD under the condition that H 2 and SiH 4 were introduced and the substrate temperature was 300 ° C. In this case, the thickness is a thickness necessary for light absorption, and is at least 500 nm or more, preferably about 10 μm. However, a thickness up to about 50 μm may be adopted. At the same time, the content of hydrogen in the layer was from 0.5 to 8%, depending on the conditions. Since the polycrystalline silicon layer 5 was formed on the silicon layer 3A that was crystallized by the metal catalyst as the substrate, the crystal orientation was the same as the crystal orientation of the silicon layer 3A, that is, (110). Compared with the direct formation of the silicon layer on a glass substrate or the like, the crystallinity was very good, and thus the composition was suitable for the solar cell device.
    [61] In addition, the 50-nm-thick n-type polycrystalline silicon layer 7 is introduced with a mixed gas composed of H 2 , SiH 4, and PH 3 (phosphine), under a pressure of 0.3 torr, and a substrate temperature of 200 ° C. It was formed on the i-type polycrystalline silicon layer 6 as the substrate by 13.56 MHz-p-CVD. The optimum thickness of this polycrystalline silicon layer 7 changes with crystallinity. However, suitable thicknesses were 10 nm to 100 nm, preferably 30 nm to 60 nm. Finally, a 1 μm thick aluminum film 8 was formed as a back electrode using vacuum deposition.
    [62] With respect to the device of the above aspect, when the surface electrode and the back electrode in the independent device on the substrate are connected in series, the 50-stage connection was performed by a conventional connection method. As a result, the characteristic is that the output voltage was almost the sum of the output voltages of the respective blocks.
    [63] In the above configuration, the substrate material includes, for example, ceramic, quartz and sapphire. Although an aluminum film was used as the back electrode, silver, molybdenum and other metals may be used.
    [64] In the configuration of the first embodiment, a glass substrate is used and light is introduced through this glass substrate. Moreover, you may employ | adopt the structure in the case of using a metal substrate instead of a glass substrate, and introducing light through the surface of a thin film. An example of this configuration is described below.
    [65] (Second embodiment)
    [66] 3 and 4 show a second embodiment of a crystalline silicon thin film semiconductor device (pin type solar cell) according to the present invention. 3 shows an intermediate step in the manufacture of the solar cell, and FIG. 4 shows the completion state of the solar cell.
    [67] A 200 nm thick Si0 2 film 10 was formed on the flexible SUS substrate 9 as an insulating film. A 500 nm thick SUS film 11 was formed on the surface of the SiO 2 film 10 as a back electrode. Next, the 10 nm-thick p-type impurity containing amorphous silicon layer 12 was sputtered on the SUS film 11 using the silicon target. The hydrogen content of the SiO 2 film 10 was 0.1% or less. In addition, the nickel salt solution was apply | coated to the surface of the amorphous silicon layer 12 by rotation, and the apply | coated thing was dried and the nickel layer 13 was formed.
    [68] The composition is then heat treated in a hydrogen atmosphere of 1 Torr at 550 ° C. for 30 minutes to crystallize the amorphous silicon layer 12, and convert the amorphous silicon layer 12 into a p-type polycrystalline silicon layer 12A. It was. At the same time, nickel in the nickel layer 13 precipitated around the boundary between the SUS film 11 and the p-type polycrystalline silicon layer 12A and hardly remained in the p-type polycrystalline silicon layer 12A. In addition, since hydrogen was practically hardly present in the p-type polycrystalline silicon layer 12A, crystallization proceeded smoothly. The 40-nm-thick p-conductive polycrystalline silicon layer 14 has a mixed gas composed of B 2 H 6 , H 2, and SiH 4 introduced onto the p-type polycrystalline silicon layer 12A, and the pressure is 0.5 Torr, It was formed by 60 MHz-p-CVD under the condition that the substrate temperature was 200 ° C. Thereafter, the 2 μm-thick i-type polycrystalline silicon layer 15 was formed by 60 MHz-p-CVD under the condition that a mixed gas composed of H 2 and SiH 4 was introduced, and the substrate temperature was 300 ° C.
    [69] In addition, the 20-nm-thick n-type polycrystalline silicon layer 16 has a mixed gas of H 2 , SiH 4, and PH 3 introduced therein, a pressure of 0.3 torr, and a substrate temperature of 300 ° C., 13.56 MHz-p. It was formed by CVD. A 70 nm thick ITO (indium tin oxide) film 17 was formed as a transparent electrode, and a metal electrode 18 having aluminum having a thickness of 1 탆 was formed on a part of the transparent electrode. In this case, the crystal orientation of each polycrystalline silicon layer 14, 15, 16 was (110). In addition, the crystal orientation of the polycrystalline silicon layer 16 may be (111) depending on the p-CVD conditions. In polycrystalline silicon having a crystal orientation of (110), its surface naturally shows a texture as compared to polycrystalline silicon having a crystal orientation of (111).
    [70] (1st comparative example)
    [71] In providing a thin film polycrystalline silicon solar cell device, a conventional method generally used is to form all polycrystalline silicon layers by p-CVD. The thin film polycrystalline silicon solar cell having the same structure as that of the first embodiment of the present invention was constructed by the method to be described in detail below, and compared with the thin film polycrystalline silicon solar cell according to the present invention.
    [72] In particular, the p-type polycrystalline silicon layer is introduced by 50 MHz-p-CVD under a condition that a mixed gas composed of H 2 , SiH 4, and B 2 H 6 is introduced, the pressure is 0.5torr, and the substrate temperature is 200 ° C. Formed. The i layer was formed by 60 MHz-p-CVD under the condition that a mixed gas composed of H 2 and SiH 4 was introduced, the pressure was 0.5 torr, and the substrate temperature was 300 ° C. n layer, H 2, SiH 4, and mixed gas is introduced consisting of PH 3, and the pressure is 0.3torr, it was formed by 13.56MHz-p-CVD under conditions with a substrate temperature of 300 ℃.
    [73] The current-voltage measurement was performed for the solar cell device thus constructed. As a result, there was a change in the curve fill factor FF as a measure of the performance of the solar cell. Here, FF = P max / (V oc × J sc ), where P max represents the maximum output, V oc represents the release voltage, and J sc represents the short-circuit photocurrent density. In particular, in the polycrystalline silicon solar cell apparatus according to the first embodiment, the filling element FF was 1.47 times that of the polycrystalline silicon solar cell apparatus of the first comparative example. Therefore, in the polycrystalline silicon solar cell apparatus according to the first embodiment of the present invention, by the use of a p layer (polycrystalline silicon layer 12A) that has been crystallized by a metal catalyst as seed crystals, all polycrystalline silicon layers are p-CVD. When formed by, the film had better characteristics than the solar cell device of the first comparative example.
    [74] (2nd comparative example)
    [75] The polycrystalline silicon solar cell apparatus of the second comparative example having the same structure as the structure according to the second embodiment of the present invention was formed by p-CVD in the same manner as in the first comparative example. The polycrystalline silicon solar cell apparatus thus obtained was compared with the polycrystalline silicon solar cell apparatus according to the second embodiment of the present invention. As a result, the filling element FF of the polycrystalline silicon solar cell apparatus according to the second embodiment of the present invention was 1.44 times that of the polycrystalline silicon solar cell apparatus of the second comparative example. Similarly to the first embodiment, the solar cell apparatus in the second embodiment of the present invention had better characteristics than that produced by the conventional method by the use of a p layer crystallized with a metal catalyst as seed crystal. .
    [76] (Third embodiment)
    [77] Next, a third embodiment of the present invention will be described. In the first and second embodiments for the amorphous silicon layers 3 and 12 crystallized by introducing a metal catalyst, the crystal orientation of the resultant crystal layer was (110). On the other hand, in the third embodiment, an 18 nm thick p-conductive impurity-containing amorphous silicon layer was formed on the transparent electrode 2 in the first embodiment, and the polycrystalline silicon layer of about 2 nm thick had a crystal orientation ( 111) was formed on the amorphous silicon layer by p-CVD in the VHF (microwave) region while introducing a mixed gas consisting of H 2 , SiH 4 and B 2 H 6 . Thereafter, a nickel layer having a thickness of about 2 nm was formed on the polycrystalline silicon layer having a crystal orientation of (111) by vacuum deposition and then heat treated at 500 ° C. for one hour. The crystal orientation of the polycrystalline silicon layer converted from the amorphous silicon layer by the heat treatment was (111). Thus, the pin structure was formed in the same manner as in the first embodiment. As a result, the crystal orientation was (111) for all the silicon layers. This solar cell apparatus according to the third embodiment was measured for electrical characteristics. Thus, it was found that the filling element FF was 0.98 times that of the solar cell apparatus according to the first embodiment of the present invention.
    [78] In the above-described embodiment, a solar cell apparatus having a fin structure is provided. However, the crystalline silicon produced according to the production method of the present invention has good characteristics, and the production of pn-type solar cells also becomes possible. This pn-type solar cell will be described as in the fourth embodiment.
    [79] (Example 4)
    [80] FIG. 5 shows a fourth embodiment of the present invention when a pn-type solar cell is formed on a glass substrate as a crystalline silicon thin film photovoltaic device. In particular, a 200 nm thick SiO 2 film 19 was formed on the glass substrate 27 as an insulating layer. In addition, the 500 nm-thick SUS film 20 was formed as a back electrode. Thereafter, a 10 nm thick n-type impurity-containing amorphous silicon layer 21 was formed by sputtering. As shown in FIG. 2 or FIG. 4, a 2 nm thick nickel catalyst layer (not shown) is formed on the amorphous silicon layer 21 and heat-treated at 500 ° C. to form the amorphous silicon layer 21 as the polycrystalline silicon layer 22A. Convert to VHF p-CVD is performed using the polycrystalline silicon layer 22A as a seed crystal to form an n-type polycrystalline silicon layer (not shown) having a thickness of 2 m. This n-type polycrystalline silicon layer was 20-100 cm <3> of resistance. In addition, a 500 nm-thick p-type polycrystalline silicon layer 23 was formed on the n-type polycrystalline silicon layer by VHF p-CVD. This p-type polycrystalline silicon layer 23 had a resistance of 0.1 to 30 m 3. In addition, an ITO film 24 having a thickness of 70 nm was formed on the p-type polycrystalline silicon layer 23 as the transparent electrode. An aluminum film 25 as an electrode was formed on the ITO film 24, and a metal electrode 26 was formed on a part of the aluminum film 25.
    [81] In the solar cell according to the fourth embodiment, 50-stage connection was performed in such a manner that the back electrode and the surface electrode were connected in series. As a result, there was a characteristic that the output voltage was the sum of the output voltages in each block.
    [82] FIG. 6 shows a fifth embodiment of the present invention in the case where a fin solar cell is formed on a glass substrate as a silicon thin film photovoltaic device. In particular, the transparent electrode 29 was formed on the glass substrate 28. SnO 2 was used as the transparent electrode 29. A nickel catalyst layer is formed on the transparent electrode 29, a 20 nm thick n-type impurity-containing amorphous silicon layer is formed, and the nickel metal catalyst layer is diffused in a nitrogen atmosphere at 550 占 폚 to crystallize the amorphous silicon layer. Thereafter, a 40-nm-thick p-type polycrystalline silicon layer 31 was formed by plasma CVD in a VHF (microwave) region while introducing a mixed gas composed of H 2 , SiH 4, and B 2 H 6 . The crystal orientation of this polycrystalline silicon layer 31 was (111). Further, the i-type polycrystalline silicon layer 32 having a thickness of 1 탆 was formed by VHF plasma CVD while introducing a mixed gas composed of H 2 and SiH 4 . The 50 nm thick n-type polycrystalline silicon layer 33 was formed by VHF plasma CVD while introducing a mixed gas consisting of PH 3 , H 2 and SiH 4 . The crystallographic orientations of the i and n layers can be (110) under certain conditions. Finally, an aluminum film 34 having a thickness of 1 탆 was formed by vacuum deposition as the back electrode. The surface of this polycrystalline silicon thin film had a textured structure suitable as a photovoltaic device. In addition, since the p layer as a substrate has a high crystallinity, the device had a much higher characteristic than when the p layer was formed directly on SnO 2 by plasma CVD.
    [83] (Third comparative example)
    [84] The solar cell apparatus of the third comparative example having the same structure as the solar cell apparatus according to the fifth embodiment was formed only by plasma CVD. The characteristics of the solar cell apparatus of the third comparative example were compared with the characteristics of the solar cell apparatus of the fifth example. As a result, the filling element FF of the solar cell apparatus of the fifth example was 1.51 times that of the solar cell apparatus of the third comparative example. Thus, by the crystallization using a metal catalyst, the solar cell apparatus of 5th Example had the characteristic which was better than the solar cell apparatus manufactured by the conventional method.
    [85] When applied to solar cells, the above-described crystalline silicon thin film semiconductor device and the crystalline silicon thin film photovoltaic device according to the present invention can be used in various applications, for example, home power systems, as well as portable equipment such as electronic calculators and watches. .
    [86] As described above, the crystalline silicon thin film semiconductor device according to the present invention introduces a metal catalyst element into an amorphous silicon layer formed on a substrate to be brought into contact with the amorphous silicon layer, and heats the amorphous silicon layer to heat the amorphous silicon layer at low temperature. And a first polycrystalline silicon layer formed by converting into a crystallographically oriented polycrystalline silicon layer through the action of a metal catalyst element, and using this first polycrystalline silicon layer as seed crystal, A second polycrystalline silicon layer formed to have a crystal orientation, and a third polycrystalline silicon layer formed using the second polycrystalline silicon layer as a substrate. By this configuration, the crystalline silicon thin film semiconductor device has high crystallinity, crystal orientation, high characteristics, and excellent productivity. In particular, thin film solar cells can be easily formed on cheap substrates such as glass substrates, and high performance crystalline silicon thin film semiconductor devices can be manufactured at low cost. In addition, silicide induced defects do not occur because silicide does not remain at the junction with other conductive types.
    [87] In the crystalline silicon thin film photovoltaic device according to the present invention, a metal catalyst element is introduced into an amorphous silicon layer formed on a substrate to be brought into contact with the amorphous silicon layer, and the amorphous silicon layer is heat-treated to heat the amorphous silicon layer at a low temperature. A first polycrystalline silicon layer formed by converting into a crystallographically oriented polycrystalline silicon layer through the action of the element, and formed on the surface of the first polycrystalline silicon layer using the first polycrystalline silicon layer as a seed crystal, A second polycrystalline silicon layer having the same crystal orientation as the silicon layer and having high crystallinity, and a third polycrystalline silicon layer formed on the second polycrystalline silicon layer and having high crystallinity and crystal orientation. By this configuration, the crystalline silicon thin film photovoltaic device has high crystallinity, excellent crystal orientation, high characteristics and excellent productivity.
    [88] In addition, the method for manufacturing a crystalline silicon thin film semiconductor device according to the present invention includes the steps of forming an amorphous silicon thin film on the surface of a substrate, introducing a metal catalyst element into an amorphous silicon layer formed on the substrate, and forming a surface portion of the amorphous silicon layer. Contacting and heat-treating the amorphous silicon layer at low temperature to crystallize the amorphous silicon layer to form a crystallographically oriented first polycrystalline silicon layer, and on the first polycrystalline silicon layer, a first polycrystalline silicon layer Using as a seed crystal to form a second polycrystalline silicon layer having the same conductivity type and crystal orientation as the first polycrystalline silicon layer, and on the second polycrystalline silicon layer, a conductivity type different from the conductivity type of the second polycrystalline silicon layer Forming a third polycrystalline silicon layer having a; By this structure, a crystalline silicon thin film semiconductor device can be manufactured to have high crystallinity, crystal orientation, high characteristics, and excellent productivity. In particular, when the present invention is applied to a thin film solar cell, an inexpensive substrate such as a glass substrate can be used. This makes it possible to manufacture high performance semiconductor devices at low cost.
    [89] While the invention has been described with reference to specific embodiments, it will be appreciated that variations and modifications can be made within the scope of the invention as set forth in the appended claims.
    权利要求:
    Claims (16)
    [1" claim-type="Currently amended] A conductive substrate or a substrate having a conductive layer on its surface,
    A crystalline phase formed by introducing a metal catalyst element into an amorphous silicon layer formed on the surface of the conductive substrate or the conductive layer and contacting the surface portion of the amorphous silicon layer, and heat treating the amorphous silicon layer to crystallize the amorphous silicon layer A first polycrystalline silicon layer oriented with
    A crystalline silicon thin film semiconductor device comprising a second polycrystalline silicon layer formed to have the same conductivity type as the first polycrystalline silicon layer by using the first polycrystalline silicon layer as a seed crystal.
    [2" claim-type="Currently amended] The method of claim 1,
    The 2nd polycrystalline silicon layer contains 0.1% or more of hydrogen, The crystalline silicon thin film semiconductor device characterized by the above-mentioned.
    [3" claim-type="Currently amended] The method of claim 1,
    The second polycrystalline silicon layer is crystallographically oriented in the thickness direction, wherein the crystalline silicon thin film semiconductor device.
    [4" claim-type="Currently amended] The method of claim 1,
    The second polycrystalline silicon layer has the same crystal orientation as the first polycrystalline silicon layer.
    [5" claim-type="Currently amended] The method of claim 1,
    And further comprising a third polycrystalline silicon layer of a second conductivity type different from the conductivity type of the second polycrystalline silicon layer, formed on the second polycrystalline silicon layer on the side distant from the first polycrystalline silicon layer. Thin film semiconductor device.
    [6" claim-type="Currently amended] The method of claim 5,
    A fourth polycrystalline silicon layer formed between the third polycrystalline silicon layer and the second polycrystalline silicon layer, the fourth polycrystalline silicon layer having a third conductivity type different from the conductivity type of the second polycrystalline silicon layer and the conductivity type of the third polycrystalline silicon layer; A crystalline silicon thin film semiconductor device characterized by the above-mentioned.
    [7" claim-type="Currently amended] The method of claim 5,
    The third polycrystalline silicon layer has the same crystal orientation as the second polycrystalline silicon layer.
    [8" claim-type="Currently amended] The method of claim 6,
    The fourth polycrystalline silicon layer has the same crystal orientation as the second polycrystalline silicon layer.
    [9" claim-type="Currently amended] The method of claim 6 or 8,
    The fourth polycrystalline silicon layer has the same crystal orientation as the third polycrystalline silicon layer.
    [10" claim-type="Currently amended] The method according to claim 5 or 6,
    The 3rd and 4th polycrystalline silicon layers contain 0.1% or more of hydrogen, The crystalline silicon thin film semiconductor device characterized by the above-mentioned.
    [11" claim-type="Currently amended] An insulating substrate having a conductive layer on the conductive substrate or surface;
    A first conductivity type formed by introducing a metal catalyst element into an amorphous silicon layer formed on the surface of the conductive substrate or the conductive layer to be brought into contact with the surface portion of the amorphous silicon layer, and heat treating the amorphous silicon layer to crystallize the amorphous silicon layer. The first polycrystalline silicon layer of,
    A second polycrystalline silicon layer formed to have the same conductivity type as the first conductivity type using the first polycrystalline silicon layer as a seed crystal;
    An i-type third polycrystalline silicon layer formed on the second polycrystalline silicon layer,
    A fourth polycrystalline silicon layer formed on the third polycrystalline silicon layer and of a second conductivity type different from the first conductivity type,
    A crystalline silicon thin film photovoltaic device comprising an electrode portion formed on a fourth polycrystalline silicon layer.
    [12" claim-type="Currently amended] The method of claim 11,
    The conductive substrate is stainless steel,
    A crystalline silicon thin film photovoltaic device, wherein the substrate having a conductive layer on the surface is glass.
    [13" claim-type="Currently amended] An insulating substrate having electrodes on its surface;
    A metal catalyst element was introduced into the amorphous silicon layer formed on the electrode of the insulating substrate to be brought into contact with the surface portion of the amorphous silicon layer, and the amorphous silicon layer was heat treated to crystallize the amorphous silicon layer to form the first conductivity type. A first polycrystalline silicon layer,
    A second polycrystalline silicon layer formed to have the same conductivity type as the first conductivity type using the first polycrystalline silicon layer as a seed crystal;
    A third polycrystalline silicon layer formed on the second polycrystalline silicon layer and being of a second conductivity type different from the first conductivity type,
    A crystalline silicon thin film photovoltaic device comprising an electrode portion formed on the third polycrystalline silicon layer.
    [14" claim-type="Currently amended] Preparing a substrate having a conductive layer on the conductive substrate or surface and forming an amorphous silicon thin film on the surface of the conductive substrate or on the surface of the conductive layer of the substrate,
    Introducing a metal catalyst element into the amorphous silicon layer to be in contact with the surface portion of the amorphous silicon layer, and heat treating the amorphous silicon layer to crystallize the amorphous silicon layer and form a crystallographically oriented first polycrystalline silicon layer; ,
    Forming a second polycrystalline silicon layer having the same conductivity type as the first polycrystalline silicon layer using the first polycrystalline silicon layer as seed crystals on the first polycrystalline silicon layer;
    A method of manufacturing a crystalline silicon thin film semiconductor device comprising forming a third polycrystalline silicon layer on the second polycrystalline silicon layer, the third polycrystalline silicon layer having a second conductivity type different from that of the second polycrystalline silicon layer.
    [15" claim-type="Currently amended] The method of claim 14,
    The amorphous silicon layer contains 0.3% or less of hydrogen, the method for producing a crystalline silicon thin film semiconductor device.
    [16" claim-type="Currently amended] The method according to claim 14 or 15,
    An amorphous silicon layer is 50 nm or less in thickness, The manufacturing method of the crystalline silicon thin film semiconductor device characterized by the above-mentioned.
    类似技术:
    公开号 | 公开日 | 专利标题
    US9548409B2|2017-01-17|Solar cell having doped semiconductor heterojunction contacts
    US10490685B2|2019-11-26|Solar cell having an emitter region with wide bandgap semiconductor material
    Varlamov et al.2013|Polycrystalline silicon on glass thin-film solar cells: A transition from solid-phase to liquid-phase crystallised silicon
    US20160111582A1|2016-04-21|Modular interdigitated back contact photovoltaic cell structure on opaque substrate and fabrication process
    EP2416373B1|2019-12-25|Solar cell
    US9093600B2|2015-07-28|Method of p-type doping of cadmium telluride
    JP3386127B2|2003-03-17|How to quickly create chalcopyrite semiconductor on a substrate
    JP2542448B2|1996-10-09|Field effect transistor and method of manufacturing the same
    AU2003220852B2|2008-12-11|Method for fabricating tandem thin film photoelectric converter
    EP0787354B1|2003-01-29|A method of manufacturing thin-film solar cells
    KR950001956B1|1995-03-07|Multi-junctional semiconductor device
    US6878921B2|2005-04-12|Photovoltaic device and manufacturing method thereof
    US5603778A|1997-02-18|Method of forming transparent conductive layer, photoelectric conversion device using the transparent conductive layer, and manufacturing method for the photoelectric conversion device
    US6339013B1|2002-01-15|Method of doping silicon, metal doped silicon, method of making solar cells, and solar cells
    US4433202A|1984-02-21|Thin film solar cell
    US5053083A|1991-10-01|Bilevel contact solar cells
    US5441577A|1995-08-15|Thin film solar cell and production method therefor
    US5262350A|1993-11-16|Forming a non single crystal semiconductor layer by using an electric current
    DE4019209C2|1992-12-17|
    KR101389546B1|2014-04-28|Method of manufacturing crystalline silicon solar cells with improved surface passivation
    US5221365A|1993-06-22|Photovoltaic cell and method of manufacturing polycrystalline semiconductive film
    US8349644B2|2013-01-08|Mono-silicon solar cells
    EP0747972B1|2002-11-27|Solar cell and manufacturing method thereof
    US7288332B2|2007-10-30|Conductive layer for biaxially oriented semiconductor film growth
    US5700333A|1997-12-23|Thin-film photoelectric conversion device and a method of manufacturing the same
    同族专利:
    公开号 | 公开日
    引用文献:
    公开号 | 申请日 | 公开日 | 申请人 | 专利标题
    法律状态:
    2001-08-24|Application filed by 히다찌 케이블 리미티드
    2001-08-24|Priority to KR1020010051387A
    2003-03-03|Publication of KR20030017202A
    优先权:
    申请号 | 申请日 | 专利标题
    KR1020010051387A|KR20030017202A|2001-08-24|2001-08-24|Crystalline silicon thin film semiconductor device, crystalline silicon thin film photovoltaic device, and process for producing crystalline silicon thin film semiconductor device|
    [返回顶部]