专利摘要:

公开号:NL2013719A
申请号:NL2013719
申请日:2014-10-31
公开日:2016-01-19
发明作者:Yu Shinn-Sheng;Lu Yen-Cheng;Yen Anthony
申请人:Taiwan Semiconductor Mfg Co Ltd;
IPC主号:
专利说明:

TITLE: EXTREME ULTRAVIOLET LITHOGRAPHY PROJECTION
OPTICS SYSTEM AND ASSOCIATED METHODS
BACKGROUND
This patent claims the benefit of U.S. Ser. No. 61/776,356 filed March 11, 2013, which is hereby incorporated by reference.
The semiconductor integrated circuit (IC) industry has experienced rapid growth. Technological advances in IC materials and design have produced generations of ICs where each generation has smaller and more complex circuits than the previous generation. In the course of IC evolution, functional density (i.e., the number of interconnected devices per chip area) has generally increased while geometry size (i.e., the smallest component (or fine) that can be created using a fabrication process) has decreased. This scaling down process generally provides benefits by increasing production efficiency and lowering associated costs. Such seating down has also increased the complexity of processing and manufacturing ICs and, for these advances to be realized, similar developments in IC processing and manufacturing are needed. For example, extreme ultraviolet (EUV) lithography systems have been implemented to perform higher resolution lithography processes. EUV lithography systems (scanners) employ radiation sources that generate fight in the EUV region. Some EUV scanners can provide 4X reduction projection printing, similar to some optical scanners, except that the EUV scanners use reflective rather than refractive optics (for example, mirrors instead of lenses). A projection optics system of the EUV lithography system typically images EUV radiation reflected from a mask onto a wafer. Because reflectivity of the mirrors in the projection optics system is limited, a source power of the EUV source that generates the EUV radiation is higher than desirable to ensure sufficient throughput, and a number of mirrors required for the resolution requirements is higher than desired. Accordingly, although existing EUV lithography systems have been generally adequate for their intended purposes, they have not been entirely satisfactory in all respects.
BRIEF DESCRIPTION OF THE DRAWINGS
The present disclosure is best understood from the following detailed description when read with the accompanying figures. It is emphasized that, in accordance with the standard practice in the industry, various features are not drawn to scale and are used for illustration purposes only. In fact, the dimensions of the various features may be arbitrarily increased or reduced for clarity of discussion. FIG. 1 is a schematic diagram of an extreme ultraviolet (EUV) lithography system for imaging a pattern of a mask onto a wafer according to various aspects of the present disclosure. FIG. 2 is a schematic diagram of a projection optics module that can be included in the EUV lithography system of FIG. 1 according to various aspects of the present disclosure.
DETAILED DESCRIPTION
The following disclosure provides many different embodiments, or examples, for implementing different features of the invention. Specific examples of components and arrangements are described below to simplify the present disclosure. These are, of course, merely examples and are not intended to be limiting. For example, the formation of a first feature over or on a second feature in the description that follows may include embodiments in which the first and second features are formed in direct contact, and may also include embodiments in which additional features may be formed between the first and second features, such that the first and second features may not be in direct contact. In addition, the present disclosure may repeat reference numerals and/or letters in the various examples. This repetition is for the purpose of simplicity and clarity and does not in itself dictate a relationship between the various embodiments and/or configurations discussed. FIG. 1 is a schematic diagram of an extreme ultraviolet (EUV) lithography system 100 for imaging a pattern of a mask onto a wafer according to various aspects of the present disclosure. In the depicted embodiment, the EUV lithography system 100 includes a radiation source module 110, an illumination module 120, a mask module 130 that includes the mask, a projection optics module 140, and a wafer module 150 that includes the wafer. The EUV lithography system 100 is designed to operate in a step-and-scan mode. FIG. 1 has been simplified for the sake of clarity to better understand the inventive concepts of the present disclosure. Additional features can be added in the EUV lithography system 100, and some of the features described below can be replaced or eliminated for additional embodiments of the EUV lithography system 100.
The radiation source module 110 includes a radiation source that generates and emits radiation (light) A. In the depicted embodiment, the radiation source emits electromagnetic radiation having a wavelength in the EUV range, for example, from about 1 nm to about 100 nm. In an example, the radiation source emits EUV radiation having a wavelength of about 13.5 nm. In an example, the radiation source is an optical source that generates ultraviolet (UV) radiation, deep UV (DUV) radiation, EUV radiation, x-ray radiation, vacuum ultraviolet (VUV) or a combination thereof. Alternatively, the radiation source is another light source designed to generate and emit radiation having a wavelength less than about 100 nm.
The illumination module 120 collects, guides, and directs the fight A, such that light A is projected onto the mask of the mask module 130. The illumination module 120 includes various optical components for collecting, directing, and shaping the fight A onto the mask. Such optical components include refractive components, reflective components, magnetic components, electromagnetic components, electrostatic components, other types of components for collecting, directing, and shaping the light A, or combinations thereof. For example, the illumination module 120 may include various condensers, lenses, mirrors, zone plates, apertures, shadow masks, and/or other optical components designed to collect, guide, and direct the light A from the radiation source module 110 onto the mask.
The mask module 130 includes a mask stage for holding the mask and manipulating a position of the mask. The mask includes a mask pattern that corresponds with a pattern of an integrated circuit device. In the present example, the mask is a reflective mask, such as a phase shift mask. The phase shift mask may be an attenuated phase shift mask (AttPSM) or an alternating phase shift mask (AltPSM). In an example, where the mask is a phase shift mask, the mask includes absorptive regions, which absorb light incident thereon, and reflective regions, which reflect light incident thereon. The absorptive regions can be configured to reflect light incident thereon with a phase different than fight reflected by the reflective regions, such that resolution and image quality of the pattern transferred to the wafer can be enhanced. The reflective and absorptive regions of the mask are patterned such that fight reflected from the reflective regions (and, in some cases, the absorptive regions) projects a mask pattern image of the mask pattern to the projection optics module 140 (and ultimately to the wafer at the wafer module 150). For example, during a lithography patterning process, the fight A is projected onto the mask of the mask module 130 via the illumination module 120, and a portion of the fight A is reflected from the mask to the projection optics module 140.
The projection optics module 140 collects, guides, and directs the fight A reflected from the mask of the mask module 130 to the wafer of the wafer module 150. The projection optics module 140 focuses the reflected fight A to form an image of the mask pattern on the wafer. In the present example, the projection optics module 140 has a magnification that is less than one, thereby reducing a size of the mask pattern image of the reflected hght A collected from the mask module 130. The projection optics module 140 includes various optical components for collecting, directing, and shaping the reflected light A onto the wafer. Such optical components include refractive components, reflective components, magnetic components, electromagnetic components, electrostatic components, other types of components for collecting, directing, and shaping the light A, or combinations thereof. In an example, the projection optics module uses Schwarzschild optics. FIG. 2 is a schematic diagram of the projection optics module 140 according to various aspects of the present disclosure. The projection optics module 140 includes less than six mirrors (designated by “M” in FIG. 2) (for example, five, four, three, or two mirrors) configured to collect, guide, and direct the light A reflected from the mask of the mask module 130 to the wafer of the wafer module 150. The five, four, three, or two mirrors are designed and configured so that the projection optics module 140 has a numerical aperture that is less than about 0.50. In an example, the numerical aperture of the projection optics module 140 is greater than or equal to 0.35 and less than about 0.50. The five, four, three, or two mirrors are further designed and configured so that an image field size of the hght A imaged at the wafer by the projection optics module 140 is greater than or equal to about 20 mm. In the depicted embodiment, the last two mirrors (M) include central obscuration, such that a pupil plane of the projection optics module 140 has a central obscuration. In an example, the shape of the pupil plane is disk-like. In an example, the central obscuration has a radius that is less than or equal to 50% of a radius of the pupil plane. In an example, the central obscuration has an area that is less than or equal to 25% of an area of the pupil plane. It is noted that, in FIG. 2, the configuration of the mirrors of the projection optics module 140 is merely exemplary, and any configuration of the mirrors of the projection optics module 140 that accomplishes the described numerical aperture, image held size, and central obscuration characteristics is contemplated by the present disclosure. It is further noted that FIG. 2 has been simplified for the sake of clarity to better understand the inventive concepts of the present disclosure. For example, the projection optics module 140 may include not illustrated refractive components, reflective components, magnetic components, electromagnetic components, electrostatic components, other types of components for cohecting, directing, and shaping the hght A, or combinations thereof.
The wafer module 150 includes a wafer stage for holding the wafer and manipulating a position of the wafer. The wafer includes a resist layer disposed over a substrate. The resist layer is sensitive to EUV radiation.
The mask pattern of the mask may be imaged onto the wafer in a repetitive fashion, although other patterning schemes are contemplated by the present disclosure.
The present disclosure provides for many different embodiments. An exemplary EUV lithography system has a projection optics system that includes less than six mirrors configured and designed to image a pattern of a mask on a wafer. The projection optics system is further configured and designed to achieve a numerical aperture less than about 0.50, an image field size of radiation imaged at the wafer that is greater than or equal to about 20 mm, and a pupil plane that includes central obscuration. In an example, the central obscuration has a radius that is less than or equal to 50% of a radius of the pupil plane. In an example, the central obscuration has an area that is less than or equal to 25% of an area of the pupil plane. Such projection optics system facilitates reduction in a power of the radiation source. In an example, the numerical aperture is greater than or equal to 0.35. In an example, the projection optics system includes at least two mirrors, where the at least two mirrors include central obscuration. The projection optics system may achieve such numerical aperture, image field size, and central obscuration using Schwarzchild optics.
In another example, an EUV lithography system includes a radiation source module; an illumination module; a mask module that includes a mask; a projection optics module; and a wafer module that includes a wafer. The radiation source module emits EUV radiation that the illumination module collects and directs to the mask, the mask reflects a portion of the EUV radiation to the projection optics module, and the projection optics module collects and directs the reflected portion of the EUV radiation to the wafer. The projection optics module includes between two to five mirrors, where the two to five mirrors are designed and configured to have a numerical aperture less than about 0.50, provide an image field size of the reflected portion of the EUV radiation imaged at the wafer that is greater than or equal to about 20 mm, and have a pupil plane that includes central obscuration. In an example, the central obscuration has a radius that is less than or equal to 50% of a radius of the pupil plane. In an example, the central obscuration has an area that is less than or equal to 25% of an area of the pupil plane. In an example, the numerical aperture is greater than or equal to 0.35. The projection optics module may include Schwarzchild optics.
In yet another example, an EUV lithography method provides a projection optics system that has between two to five mirrors, wherein the two to five mirrors are designed and configured to have a numerical aperture less than about 0.50, provide an image field size of EUV radiation imaged at a wafer that is greater than or equal to about 20 mm, and have a pupil plane that includes central obscuration; illuminates a mask with EUV radiation; and collects, by the projection optics system, EUV radiation reflected from the mask, where the collected EUV radiation is reflected from the two to five mirrors before being imaged on the wafer by the projection optics system. The EUV radiation has a wavelength of about 1 nm to about 100 nm. In an example, the collected EUV radiation travels through a central obscuration of at least two mirrors before being imaged on the wafer.
In an example, the numerical aperture is also greater than or equal to about 0.35.
The foregoing outhnes features of several embodiments so that those skilled in the art may better understand the aspects of the present disclosure. Those skilled in the art should appreciate that they may readily use the present disclosure as a basis for designing or modifying other processes and structures for carrying out the same purposes and/or achieving the same advantages of the embodiments introduced herein.
Those skilled in the art should also reahze that such equivalent constructions do not depart from the spirit and scope of the present disclosure, and that they may make various changes, substitutions, and alterations herein without departing from the spirit and scope of the present disclosure.
权利要求:
Claims (20)
[1]
1, An extreme ultraviolet (EUV) lithographic system, comprising: a projection option system with fewer than six mirrors configured and designed to extract a pattern from a mask on a wafer, which projection option system is further arranged and designed to achieve the following : a numerical aperture less than 0.50; an image field size of radiation imaged on the wafer that is greater than or equal to 20 mm; and a pupil face with a central eclipse, with the two closest to the wafer having the central eclipse.
[2]
The EUV lithographic system according to claim 1, wherein the numerical aperture is greater than or equal to 0.35.
[3]
3, The EUV lithographic system according to claim 1, wherein the projection option system comprises at least two mirrors,
[4]
4, The EUV lithographic system according to claim 3, the mirrors being at least two mirrors with central darkening.
[5]
The EUV lithographic system according to claim 1, wherein the central eclipse has a radius that is less than or equal to 50% of the radius of the pupil surface.
[6]
The EUV lithographic system according to claim 1, wherein the central eclipse has an area that is less than or equal to 25% of an area of the pupil surface.
[7]
The EUV lithographic system according to claim 1, wherein the projection optics system comprises Schwarzchild optics.
[8]
The EUV lithographic system according to claim 1, wherein the radiation imaged on the wafer has a wavelength of 1 nm to 100 nm.
[9]
The EUV lithographic system according to claim 1, wherein the radiation imaged on the wafer has a wavelength of 13.5 nm.
[10]
The EUV lithographic system according to claim 1, wherein the mask is a reflective mask.
[11]
An extreme ultraviolet (EUV) lithographic system comprising: a radiation source module; a lighting module; a mask module comprising a mask; a projection optics module; a wafer module comprising a wafer; wherein the radiation source module emits EUV radiation that the lighting module collects and sends to the mask, the mask reflecting a portion of the EUV radiation to the projection optics module and the projection optics module collecting the reflected portion of the EUV radiation and sending it to the wafer; and wherein the projection optics module further comprises two to five mirrors, wherein the two to five mirrors are designed and oriented to have a numerical aperture of less than 0.50, to provide an image field size of the reflected portion of the EUV radiation being depicted on the wafer greater than or equal to 20 mm, and to provide a pupil face with central darkening, with the two mirrors closest to the wafer having the central darkening.
[12]
The EUV lithographic system according to claim 11, wherein the central eclipse has a radius that is less than or equal to 50% of the radius of the pupil surface.
[13]
The EUV lithographic system according to claim 11, wherein the central eclipse has an area that is less than or equal to 25% of an area of the pupil surface.
[14]
The EUV lithographic system according to claim 11, wherein the numerical aperture is greater than or equal to 0.35.
[15]
The EIJV lithographic system according to claim 11, wherein the projection optics module comprises Schwarzchild optics.
[16]
The EUV lithographic system according to claim 11, wherein the EUV radiation has a wavelength of 13.5 nm.
[17]
An extreme ultraviolet (EUV) lithographic method comprising: providing a projection optics system with two to five mirrors, the two to five mirrors being designed and arranged to have a numerical aperture of less than 0.50, providing a image field size of EUV radiation imaged on a wafer that is greater than or equal to 20 mm, and having a pupil plane with central obscuration; illuminating a mask with EUV radiation; and collecting by the projection optics system masked EUV radiation, wherein the collected EUV radiation is reflected by the two to five mirrors before being imaged on the wafer by the projection optics system, with the mirrors, the two closest have the central eclipse at the wafer.
[18]
The EUV lithographic method according to claim 17, wherein the EUV radiation has a wavelength of 1 nm to 100 nm.
[19]
The EUV lithographic method according to claim 17, wherein the collected EUV radiation passes through a central eclipse of at least two mirrors before being imaged on the wafer.
[20]
The EUV lithographic method according to claim 17, wherein the numerical aperture is greater than or equal to about 0.35.
类似技术:
公开号 | 公开日 | 专利标题
NL2013719B1|2016-04-04|Extreme ultraviolet lithography projection optics system and associated methods.
KR100589236B1|2006-06-14|Lithographic projection apparatus and reflector assembly for use in said apparatus
US20160306282A1|2016-10-20|Collector in an Extreme Ultraviolet Lithography System with Optimal Air Curtain Protection
KR100696736B1|2007-03-20|Lithographic Projection Apparatus with Collector including Concave and Convex Mirrors
US6576912B2|2003-06-10|Lithographic projection apparatus equipped with extreme ultraviolet window serving simultaneously as vacuum window
US8018578B2|2011-09-13|Pellicle, lithographic apparatus and device manufacturing method
KR101572930B1|2015-11-30|Radiation system, radiation collector, radiation beam conditioning system, spectral purity filter for a radiation system and method of forming a spectral purity filter
JP6420864B2|2018-11-07|Spectral purity filters, radiation systems, and collectors
JP2006332654A|2006-12-07|Radiation system and lithographic device
KR100536631B1|2005-12-14|Illumination system for extreme ultraviolet radiation and its application in lithographic projection apparatus
US9442384B2|2016-09-13|Extreme ultraviolet lithography process and mask
JP5081194B2|2012-11-21|Lithographic apparatus
JP2012506133A|2012-03-08|Collector assembly, radiation source, lithographic apparatus and device manufacturing method
EP1469349A1|2004-10-20|Lithographic projection apparatus with collector including a concave mirror and a convex mirror
US20120013882A1|2012-01-19|Illumination system, lithographic apparatus and method of forming an illumination mode
JP2002198309A5|2005-10-27|
US20190146362A1|2019-05-16|Lithography system having invisible pellicle over mask
US20200166855A1|2020-05-28|Control of reticle placement for defectivity optimization
US20110170083A1|2011-07-14|Lithographic Apparatus and Device Manufacturing Method
US8405825B2|2013-03-26|Method of detecting a particle and a lithographic apparatus
CN104914678B|2017-10-20|Extreme ultraviolet lithography projection optical system and correlation technique
JP2011150227A|2011-08-04|Exposure device and device manufacturing method
NL2007629A|2011-11-23|Optical apparatus for conditioning a radiation beam for use by an object, lithography apparatus and method of manufacturing devices.
NL2005516A|2011-06-21|Lithographic apparatus and device manufacturing method.
同族专利:
公开号 | 公开日
US20140253892A1|2014-09-11|
TW201535058A|2015-09-16|
NL2013719B1|2016-04-04|
引用文献:
公开号 | 申请日 | 公开日 | 申请人 | 专利标题
US5212588A|1991-04-09|1993-05-18|The United States Of America As Represented By The United States Department Of Energy|Reflective optical imaging system for extreme ultraviolet wavelengths|
US20130070227A1|2010-08-25|2013-03-21|Carl Zeiss Smt Gmbh|Imaging optical system|
US6331710B1|1998-12-02|2001-12-18|Zhijiang Wang|Reflective optical systems for EUV lithography|US10712671B2|2016-05-19|2020-07-14|Nikon Corporation|Dense line extreme ultraviolet lithography system with distortion matching|
US11054745B2|2017-04-26|2021-07-06|Nikon Corporation|Illumination system with flat 1D-patterned mask for use in EUV-exposure tool|
CN110914760A|2017-05-11|2020-03-24|株式会社尼康|Illumination system with curved one-dimensional patterned mask for EUV exposure tool|
US10295911B2|2016-05-19|2019-05-21|Nikon Corporation|Extreme ultraviolet lithography system that utilizes pattern stitching|
CN110753882A|2017-04-19|2020-02-04|株式会社尼康|Optical objective operating in the EUV spectral region|
US11067900B2|2016-05-19|2021-07-20|Nikon Corporation|Dense line extreme ultraviolet lithography system with distortion matching|
US10890849B2|2016-05-19|2021-01-12|Nikon Corporation|EUV lithography system for dense line patterning|
US10527956B2|2017-03-24|2020-01-07|Nikon Corporation|Temperature controlled heat transfer frame for pellicle|
US10586709B2|2017-12-05|2020-03-10|Samsung Electronics Co., Ltd.|Methods of fabricating semiconductor devices|
US11043239B2|2019-03-20|2021-06-22|Kla Corporation|Magneto-optic Kerr effect metrology systems|
法律状态:
优先权:
申请号 | 申请日 | 专利标题
US201361776356P| true| 2013-03-11|2013-03-11|
US14/203,348|US20140253892A1|2013-03-11|2014-03-10|Extreme Ultraviolet Lithography Projection Optics System and Associated Methods|
[返回顶部]