DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Claim Rejections - 35 USC § 102
The following is a quotation of the appropriate paragraphs of 35 U.S.C. 102 that form 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.
Claim(s) 10, 12, 15, are 16 is/are rejected under 35 U.S.C. 102a1 as being anticipated by Hamann (US 2005/0112896).
Regarding claim 10.
Hamann teaches a structure comprising: a top electrode and a bottom electrode (10,55) (fig 4); and a multilayer stack disposed between the top electrode and the bottom electrode (10,55), wherein the multilayer stack comprises alternating confinement layers (20,30,40) and phase-change material layers (15,25,35,45), and wherein at least two of the phase-change material layers have different thicknesses (fig 4), wherein a first phase-change material layer (15) proximate to the bottom electrode (10) has a thinner thickness than a second phase-change material layer (45) proximate to the top electrode (55) (fig 4) (paragraph 37-43).
Regarding claim 12.
Hamann teaches the different thicknesses result in variable resistance through the multilayer stack (paragraph 28,29).
Regarding claim 15.
Hamann teaches the phase-change material layers comprise a similar crystallinity temperature (Tc) (Tc is a property of the material, the layers have similar composition GST and therefore similar Tc).
Regarding claim 16.
Hamann teaches the confinement layers (20,30,40) comprise one or more selected from a group consisting of: Ti(Se, Te)2, Tantalum Nitride (TaN), Carbon (C), Tantalum Aluminum Nitride (TaAIN), Tantalum Silicon Nitride (TaSiN), Titanium Aluminum Nitride (TiAIN), Titanium Silicon Nitride (TiSiN), Titanium Nitride (TiN), Silicon (Si) (paragraph 27).
Claim Rejections - 35 USC § 103
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.
Claim(s) 1 through 7 is/are rejected under 35 U.S.C. 103 as being unpatentable over Hamann (US 2005/0112896) in view of Wu (US 2021/0249592)
Regarding claim 1.
Hamaan teaches a structure comprising: a top electrode (10) and a bottom electrode (55); and a multilayer stack disposed between the top electrode (10) and the bottom electrode (55), wherein the multilayer stack comprises alternating confinement layers (20,30,40) and phase-change material layers (15,25,35), and wherein at least two of the phase-change material layers (15,25,35) have different [properties] (fig 3-8) (paragraph 26-31).
PNG
media_image1.png
250
430
media_image1.png
Greyscale
Hamann does not teach that the phase change materials vary in dopant concentration.
Wu teaches a structure comprising: a top electrode (142) and a bottom electrode (140); and a multilayer stack (130) disposed between the top electrode and the bottom electrode, wherein the multilayer stack comprises phase-change material layers, and wherein at least two of the phase-change material layers have different doping concentrations of at least one dopant (fig 4c) (paragraph 54-55).
It would have been obvious to one of ordinary skill in the art to vary the germanium concentration of the GST sublayers in order to improve the retention characteristics of the device (paragraph 48)
Regarding claim 2.
Wu teaches the at least two of the phase-change material layers (130a,b,c) have different doping concentrations of different dopants (paragraph 47,53).
Regarding claim 3.
Hamann teaches a first phase-change material layer (45) proximate to the bottom electrode (55) has a higher resistance than a second phase-change material layer (15) proximate to the top electrode (10) (paragraph 28).
Regarding claim 4.
Hamann teaches the different doping concentrations result in variable resistance through the multilayer stack (paragraph 29).
Wu teaches the different doping concentrations result in variable resistance through the multilayer stack (resistivity of GST is inherently directly proportional to the germanium concentration).
Regarding claim 5.
Hamann teaches the phase-change material layers comprise a similar crystallinity temperature (Tc) (Tc is a property of the material, the layers have similar composition GST and therefore similar Tc).
Regarding claim 6.
Hamann teaches the different doping concentrations comprise doping by at least one dopant selected from a group consisting of: Germanium (Ge), Nitrogen (N), Silicon (Si), Selenium (Se), Tantalum (Ta), Silicon Dioxide (Si02), Carbon (C), and Aluminum Nitride (AIN) (paragraph 29).
Wu teaches the different doping concentrations comprise doping by at least one dopant selected from a group consisting of: Germanium (Ge), Nitrogen (N), Silicon (Si), Selenium (Se), Tantalum (Ta), Silicon Dioxide (S102), Carbon (C), and Aluminum Nitride (AIN) (paragraph 47-53).
Regarding claim 7.
Haman teaches the confinement layers (20,30,40) comprise one or more selected from a group consisting of: Ti(Se, Te)2, Tantalum Nitride (TaN), Carbon (C), Tantalum Aluminum Nitride (TaAIN), Tantalum Silicon Nitride (TaSiN), Titanium Aluminum Nitride (TiAIN), Titanium Silicon Nitride (TiSiN), Titanium Nitride (TiN), Silicon (Si) (paragraph 27).
Claim(s) 8 and 9 is/are rejected under 35 U.S.C. 103 as being unpatentable over Hamann (US 2005/0112896) in view of Wu (US 2021/0249592) as applied to claim 1 and further in view of Gotti (US 2015/0028284)
Regarding claim 8
Hamann in view of Wu teaches elements of the claimed invention above.
Hamann in view of Wu does not teach thicknesses.
Gotti teaches each layer (210,211) in the multilayer stack has a thickness of 1-20 nanometers (nm) (paragraph 26,29) (fig 2).
It would have been obvious to one of ordinary skill in the art for each layer to be of 1-20 nanometers (nm) thick in order to provide sufficient resistance variation and diffusion prevention.
Regarding claim 9.
Hamann in view of Wu teaches elements of the claimed invention above.
Hamann in view of Wu does not teach thicknesses.
Gotti teaches the multilayer stack (209) has a thickness of 20-200 nanometers (nm) (paragraph 26,29).
It would have been obvious to one of ordinary skill in the art for each layer to be of 1-20 nanometers (nm) thick totaling 20-200nm in order to provide sufficient resistance variation and diffusion prevention.
Claim(s) 13 and 14 is/are rejected under 35 U.S.C. 103 as being unpatentable over Hamann (US 2005/0112896) as applied to claim 10 and further in view of Allegra (US 2018/0358094).
Regarding claim 13.
Hamann teaches elements of the claimed invention above.
Hamann does not teach that two confinement layers have different thicknesses.
Allegra teaches at least two of the confinement layers (416,412-1,412-2) have different thicknesses (fig 3) (paragraph 65,81).
It would have been obvious to one of ordinary skill in the art to provide confinement layers of different thickness in order to control the electrode resistance as a parameter of controlling the device charecteristics
Regarding claim 14.
Gotti teaches a first confinement layer (205-b) proximate to the bottom electrode (205-a) has a thinner thickness than a second confinement layer (205-c) proximate to the top electrode (205-d) (fig 3) (paragraph 81) (note a thinner layer will have less resistance than a thicker layer).
Claim(s) 13 and 14 is/are rejected under 35 U.S.C. 103 as being unpatentable over Hamann (US 2005/0112896) as applied to claim 10 and further in view of Gotti (US 2015/0028284).
Regarding claim 13.
Hamann teaches elements of the claimed invention above.
Hamann does not teach that two confinement layers have different thicknesses.
Gotti teaches at least two of the confinement layers (416,412-1,412-2) have different thicknesses (fig 3,4) (paragraph 44-48).
It would have been obvious to one of ordinary skill in the art to provide confinement layers of different thickness in order to act as diffusion barriers and modulate the grain sizes of the phase change materials (Gotti paragraph 11)
Regarding claim 14.
Gotti teaches a first confinement layer (416) proximate to the bottom electrode (412-1) has a thinner thickness than a second confinement layer (412-2) proximate to the top electrode (410) (fig 4) (paragraph 47-50).
Claim(s) 17 and 18 is/are rejected under 35 U.S.C. 103 as being unpatentable over Hamann (US 2005/0112896) as applied to claim 10 and further in view of Gotti (US 2015/0028284)
Regarding claim 17
Hamann teaches elements of the claimed invention above.
Hamann does not teach thicknesses.
Gotti teaches each layer (210,211) in the multilayer stack has a thickness of 1-20 nanometers (nm) (paragraph 26,29) (fig 2).
It would have been obvious to one of ordinary skill in the art for each layer to be of 1-20 nanometers (nm) thick in order to provide sufficient resistance variation and diffusion prevention.
Regarding claim 18.
Hamann teaches elements of the claimed invention above.
Hamann does not teach thicknesses.
Gotti teaches the multilayer stack (209) has a thickness of 20-200 nanometers (nm) (paragraph 26,29).
It would have been obvious to one of ordinary skill in the art for each layer to be of 1-20 nanometers (nm) thick totaling 20-200nm in order to provide sufficient resistance variation and diffusion prevention.
Claim(s) 19 and 20 is/are rejected under 35 U.S.C. 103 as being unpatentable over Hamann (US 2005/0112896) in view of Wu (US 2021/0249592)
Regarding claim 19.
Hamann teaches
A structure comprising: a top electrode and a bottom electrode (10,55); and a multilayer stack (15-45) disposed between the top electrode and the bottom electrode (10,55), wherein the multilayer stack comprises alternating confinement layers (20,30,40) and phase-change material layers (15,25,35,45), and wherein at least two of the phase-change material layers have different thicknesses (fig 4) (paragraph 37-43).
Hamann does not teach that the phase change materials vary in dopant concentration.
Wu teaches a structure comprising: a top electrode (142) and a bottom electrode (140); and a multilayer stack (130) disposed between the top electrode and the bottom electrode, wherein the multilayer stack comprises phase-change material layers, and wherein at least two of the phase-change material layers have different doping concentrations of at least one dopant (fig 4c) (paragraph 54-55).
It would have been obvious to one of ordinary skill in the art to vary the germanium concentration of the GST sublayers in order to improve the retention characteristics of the device (paragraph 48)
Regarding claim 20
Hamann teaches a first phase-change material layer (45) proximate to the bottom electrode (55) has a higher resistance than a second phase-change material layer (15) proximate to the top electrode (10) (paragraph 28).
Response to Arguments
Applicant’s arguments with respect to claim(s) have been considered but are moot because the new ground of rejection does not rely on any reference applied in the prior rejection of record for any teaching or matter specifically challenged in the argument.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to DAVID J GOODWIN whose telephone number is (571)272-8451. The examiner can normally be reached Monday - Friday, 11:00 - 19:00.
Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Kretelia Graham can be reached on (571)272-5055. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000.
/D.J.G/Examiner, Art Unit 2817
/KYOUNG LEE/Primary Examiner, Art Unit 2817
Prosecution Insights