DETAILED ACTION
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Claims 1-20 are pending.
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claims 16 and 17 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
Claim 16 recites the limitation " the PAB" in line 2, and claim 17 recites the limitation “the PAB” on line 1.
However, claims 16 and 17 depend on claim 13 which recites “a first PAB” and “a second PAB” and it is not clear to which PAB are claims 16 and 17 referring to.
Therefore, it is not clear what is the joint inventor claiming as the inventions in claims 16 and 17 of the instant application.
Claim Rejections - 35 USC § 102
The following is a quotation of the appropriate paragraph of 35 U.S.C. 102 that forms the basis for the rejections under this section made in this Office action:
A person shall be entitled to a patent unless –
(a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention.
Claims 1-10 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Wang et al. (US 2006/0094131).
With regard to claims 1 and 6, Wang et al. teach a process comprising steps of: applying a photoresist layer on a wafer (102), baking (108), and obtaining critical dimension (CD) measurement (110) (fig.1, par.0016-0018). The CD measurement may be obtained using optical digital profilometry (ODP), which is an optical nondestructive, inline measurement technique (par.0017).
The step of obtaining critical dimension (CD) measurement of Wang et al. is a step of “measuring properties of the photoresist layer with an optical tool” in claim 1.
Fig.1 of Wang et al. shows that the step of obtaining critical dimension (CD) measurement is performed after the baking steps, as required in claim 6.
Therefore, the process of Wang et al. anticipates the methods in claims 1 and 6.
With regard to claims 2 and 3, Wang et al. teach that the optical digital profilometry (ODP), tool is paired with a spectroscopic ellipsometer (par.0018).
A spectroscopic ellipsometer may use light with a wavelength of 400-750 nm, as evidenced in column 5, lines 1-8 of McGahan (US Patent 6,381,009).
With regard to claims 4 and 10, Wang et al. teach that the values for thickness or refractive index may be obtained (par.0018).
The thickness of a photoresist layer determines the sensitivity to light exposure (see column 1, lines 70-71 of Middelhoek et al. (US Patent 3,669,732)).
With regard to claim 5, Wang et al. teach that the CD information is extracted from a period grating structure on the semiconductor device (par.0018). (102)
With regard to claim 7, fig.6 shows the components of the semiconductor processing system including resist coating component (602), pre-baking component (604), baking component (608), CD analysis tool (612) (par.0024). The various components may be separate pieces of processing equipment (par.0024).
With regard to claim 8, Wang et al. teach that the step of obtaining critical dimension (CD) measurement (110) may be performed simultaneously with the baking step (108)(par.0019).
With regard to claim 9, fig.6 shows the components of the semiconductor processing system including resist coating component (602), pre-baking component (604), baking component (608), CD analysis tool (612) (par.0024). The various components may be combined into a single piece of equipment (par.0024).
7. Claims 1-4, 6, 7, 10, and 12 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Wong et al. (US Patent 6,319,655).
With regard to claims 1, 2, 4, and 6, Wong et al. teach that a 193nm photoresist is spin-coated onto a blank silicon substrate. The photoresist layer and the substrate are soft baked at 140oC for 60 seconds on a hot plate to drive off most of the solvent. After the soft-bake the thickness was about 6,000 Angstrom. Each photoresist film was measured with a J.A. Woolam spectroscopic ellipsometer to obtain post-coat thickness and optical constants. FTIP spectroscopy was also performed to obtain infrared spectra of each film (Example 2 in columns 9 and 10).
The spin-coating of the photoresist layer on a blank silicon substrate of Wong et al. is the step of “depositing the photoresist layer on a substrate” in claim 1.
The soft-bake step of Wong et al. is the step of “baking the photoresist layer” in claim 1.
The spectroscopic ellipsometer is an optical tool in claim 1, and meets the limitations of claim 2.
Measuring the thickness with the spectroscopic ellipsometer of Wong et al. is the step of “measuring properties of the photoresist layer with an optical tool” in claim 1, and meets the limitation of claim 4.
The measurement of thickness occurs after the soft-bake step, as required
in claim 6.
With regard to claim 3, a spectroscopic ellipsometer may use light with a wavelength of 400-750 nm, as evidenced in column 5, lines 1-8 of McGahan (US Patent 6,381,009).
With regard to claim 7, Wong et al. teach that the soft-bake is performed on a hot plate and the measuring of thickness is performed with a J.A. Woolam spectroscopic ellipsometer (Example 2 in columns 9 and 10). This shows that the optical tool is a distinct tool apart from the tool used for soft-bake.
With regard to claim 10, the thickness of a photoresist layer determines the sensitivity to light exposure, as evidenced in column 1, lines 70-71 of Middelhoek et al. (US Patent 3,669,732).
With regard to claim 12, Wong et al. teach that the 193nm photoresist is a chemically amplified resist (column 2, lines 17-31).
Claim Rejections - 35 USC § 103
8. The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
9. Claim 11 is rejected under 35 U.S.C. 103 as being unpatentable over Wang et al. (US 2006/0094131) in view of Srivastava et al. (US 2018/0158723).
With regard to claim 11, Wang et al. teach the method of claim 1 (see paragraph 6 above), but fail to specifically teach that the photoresist is a metal oxo photoresist material.
However, it is well-known that a metal oxide photoresist can be directly patterned using an exposure source and can be etched with a higher selectivity than organic films, such as conventional photoresist (see par.0012 of Srivastava et al.).
Therefore, it would have been obvious to one of ordinary skill in the art before the filing date of the claimed invention to use a metal oxide photoresist in the process of Wang et al., in order to take advantage of its higher selectivity in an etching step.
10. Claim 12 is rejected under 35 U.S.C. 103 as being unpatentable over Wang et al. (US 2006/0094131) in view of Choi (US Patent 6,045,970).
With regard to claim 12, Wang et al. teach the method of claim 1 (see paragraph 6 above), but fail to specifically teach that the photoresist is a chemically amplified resist (CAR).
However, it is well-known in the art that a chemically amplified resist (CAR) has higher sensitivity to light source irradiation than conventional resist (see column 1, lines 25-33 of Choi).
Therefore, it would have been obvious to one of ordinary skill in the art before the filing date of the claimed invention to use a chemically amplified resist (CAR) in the process of Wang et al., in order to take advantage of its improved sensitivity.
11. Claims 13 and 17 are rejected under 35 U.S.C. 103 as being unpatentable over Wong et al. (US Patent 6,319,655) as evidenced by Middelhoek et al. (US Patent 3,669,732) and in view of Saito (US 2008/0213677).
With regard to claim 13, Wong et al. teach that a 193nm photoresist is spin-coated onto a blank silicon substrate. The photoresist layer and the substrate are soft baked at 140oC for 60 seconds on a hot plate to drive off most of the solvent. After the soft-bake the thickness was about 6,000 Angstrom. Each photoresist film was measured with a J.A. Woolam spectroscopic ellipsometer to obtain post-coat thickness and optical constants. FTIP spectroscopy was also performed to obtain infrared spectra of each film (Example 2 in columns 9 and 10).
The spin-coating of each photoresist on a blank silicon substrate of Wong et al. meets the limitations for the steps of “depositing a first photoresist layer on a first substrate” and “depositing a second photoresist layer on a second substrate” in claim 13.
The soft-bake of each photoresist of Wong et al. meets the limitations for the steps of “baking the first photoresist layer with a first PAB” and “baking the second photoresist layer with a second PAB” in claim 13.
The spectroscopic ellipsometer is an optical tool in claim 13.
Measuring the thickness of each photoresist layer with the spectroscopic ellipsometer of Wong et al. meets the limitations for the steps of “measuring a material property of the first photoresist layer after the first PAB with an optical tool” and “measuring a material property of the second photoresist layer after the second PAB with the optical tool” in claim 13,
The thickness of a photoresist layer determines the sensitivity to light exposure, as evidenced in column 1, lines 70-71 of Middelhoek et al. (US Patent 3,669,732).
Therefore, photoresist with different thickness and different sensitivities may be prepared.
Wong et al. and Middelhoek et al. fail to teach the selecting step in claim 13.
However, it is well-known in the art that a plurality of resists different in sensitivity may be prepared and the resist having sensitivity necessary and sufficient to form desired pattern dimensions may be selected (see par.0033 of Saito).
Therefore, it would have been obvious to one of ordinary skill in the art before the filing date of the claimed invention to select the resist having sensitivity necessary and sufficient to form desired pattern dimensions from the plurality of prepared photoresists of Wong et al.
With regard to claim 17, the soft-bake occurs before the exposure and development (Example 2 in columns 9 and 10), so optimizing the soft-bake happens without exposing and developing the photoresist layers.
12. Claims 13-16 are rejected under 35 U.S.C. 103 as being unpatentable over Wang et al. (US 2006/0094131) in view of Middelhoek et al. (US Patent 3,669,732).
With regard to claim 13, Wang et al. teach a process comprising steps of: applying a photoresist layer on a wafer (102), baking (108), and obtaining critical dimension (CD) measurement (110) (fig.1, par.0016-0018). The CD measurement may be obtained using optical digital profilometry (ODP), which is an optical nondestructive, inline measurement technique (par.0017).
The step of obtaining critical dimension (CD) measurement of Wang et al. is a step of “measuring a material property of the first photoresist layer with an optical tool” in claim 1.
Wang et al. teach that the step of obtaining critical dimension (CD) measurement (110) may be performed simultaneously with the baking step (108)(par.0019).
Wang et al. further teach an optical digital profilometry (ODP) library(fig.7, par.0025), which implies that a process comprising steps of applying a photoresist layer on a wafer (102), baking (108), and obtaining critical dimension (CD) measurement (110) is repeated and the results of optical digital profilometry (ODP) are stored in a library.
Wang et al. do not teach the step of “selecting the photoresist layer with the material property that provides the most desirable line edge roughness, line edge roughness and/or sensitivity to radiation exposure”
However, Wang et al. teach that the values for thickness or refractive index may be obtained (par.0018).
It is known in the art that the thickness of a photoresist layer determines the sensitivity to light exposure (see column 1, lines 70-71 of Middelhoek et al. (US Patent 3,669,732)).
Therefore, it would have been obvious to one of ordinary skill in the art before the filing date of the claimed invention to use the results of optical digital profilometry (ODP) library of Wang et al. and select the photoresist layer with the thickness that provides the desired sensitivity the radiation exposure.
With regard to claim 14, Wang et al. fail to teach that the baking steps are done at different temperatures.
However, there are only two possibilities: the baking steps are performed at the same temperature or the baking steps are performed at different temperatures.
Therefore, it would have been obvious to one of ordinary skill in the art before the filing date of the claimed invention to perform the baking steps (108) of Wang et al. at different temperatures, with a reasonable expectation of success.
With regard to claim 15, Wang et al. fail to teach that the baking steps are done for different durations.
However, there are only two possibilities: the baking steps have the same duration or the baking steps have different durations.
Therefore, it would have been obvious to one of ordinary skill in the art before the filing date of the claimed invention to perform the baking steps (108) of Wang et al. at for different durations, with a reasonable expectation of success.
With regard to claim 16, fig.6 of Wang et al. shows the components of the semiconductor processing system including resist coating component (602), baking component (608), CD analysis tool (612) (par.0024). The various components may be combined into a single piece of equipment (par.0024).
13. Claims 18-20 are rejected under 35 U.S.C. 103 as being unpatentable over Wang et al. (US 2006/0094131) in view of Houshmand et al. (WO 2022/108773 A1).
With regard to claim 18, Wang et al. teach a semiconductor processing system comprising a component (602) for coating a resist on a wafer, a pre-baking component (604), and a critical dimension (CD) analysis tool (612) to obtain CD information (fig.6, par.0024). The CD measurement may be obtained using optical digital profilometry (ODP), which is an optical nondestructive, inline measurement technique (par.0017).
Wang et al. fail to teach the dry deposition of the photoresist layer on a wafer.
However, it is well-known in the art that a photoresist may be deposited by a chemical vapor deposition (CVD) process, plasma enhanced CVD (PE-CVD), atomic layer deposition (ALD) process, or plasma enhanced ALD (PE-ALD) process (see claim 15 of Houshmand et al.).
Therefore, it would have been obvious to one of ordinary skill in the art before the filing date of the claimed invention to use a chemical vapor deposition (CVD) process, plasma enhanced CVD (PE-CVD), atomic layer deposition (ALD) process, or plasma enhanced ALD (PE-ALD) process for coating the photoresist of Wang et al. on a wafer.
A chemical vapor deposition (CVD) process, plasma enhanced CVD (PE-CVD), atomic layer deposition (ALD) process, and plasma enhanced ALD (PE-ALD) process are dry deposition processes, as defined in par.0029 of the specification of the instant application.
With regard to claim 19, Wang et al. teach that the optical digital profilometry (ODP), tool is paired with a spectroscopic ellipsometer (par.0018).
With regard to claim 20, a chemical vapor deposition (CVD) process, aplasma enhanced CVD (PE-CVD) process, atomic layer deposition (ALD) process, and a plasma enhanced ALD (PE-ALD) process meet the claim limitations.
Conclusion
14. The prior art made of record and not relied upon is considered pertinent to applicant's disclosure:
Poris (US Patent 5,625,170) teaches that the thickness of the photoresist layer is determined using an optical tool (column 13, lines 2-4).
Nikkonahad et al. (US 2002/0180986) teach that a spectroscopic ellipsometer may be coupled to a lithography track. A processor may be coupled to the spectroscopic ellipsometer, and the processor may be configured to determine at least one property of the specimen, such as a critical dimension, a profile, a thickness. The spectroscopic ellipsometer may be configured to direct light and detect light returned from the specimen during a process performed in the process chamber. The process may be a post-apply bake process (par.0537).
Paniez et al. (“Study of Bake Mechanisms by Real-Time In-Situ Ellipsometry”) teach that ellipsometry is a well-known characterization technique and two parameters namely Psi and Delta are measured. From Psi and Delta film thickness and refractive index (RI) are calculated using a mono or multilayer model depending on the film characteristics (“Experimental” on page 289).
A resist solution allowed the formation of films with a thickness of 3mm at 3000 rpm. Psi/Delta curve is described during a soft-bake step at 100oC (“3.1. Pure Polymer Films” on page 290”).
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/ANCA EOFF/Primary Examiner, Art Unit 1722
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