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 § 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.
Claims 1-5 and 7 are rejected under 35 U.S.C. 103 as being unpatentable over Seo et al. (United States Patent Application Publication No. US 2016/0148947 A1, hereinafter “Seo”) as further evidenced by Yamazaki et al. (USPN 5,308,998, hereinafter “Yamazaki”) in view of Shin et al. (United States Patent Application Publication No. US 2016/0343729 A1, hereinafter “Shin”) and further in view of Kim et al. (United States Patent Application Publication No. US 2014/0070283 A1, hereinafter “Kim) and as further evidenced by Lin et al. (United States Patent Application Publication No. US 2018/0114871 A1, hereinafter “Lin”).
In reference to claim 1, Seo discloses a similar device. Figures 1-13D of Seo disclose an apparatus which has a stack comprising alternating conductive structures (GL) and insulative structures (125). A channel (121) vertically extends through the stack. An outer oxide material (BCL – p. 4-5, paragraph 57) extends vertically through the channel (121) and is laterally adjacent to opposing sidewalls of the channel (121). A nitride material (CL – p. 5, paragraph 58) extends vertically through the channel (121) and is laterally adjacent to the outer oxide material (BCL). An inner oxide material (TL – p. 5, paragraph 59) extends vertically through the channel (121) and is laterally adjacent to the nitride material (CL). A channel material (135, 136) extends vertically through the stack and is laterally adjacent to the inner oxide material (TL) and exhibits a first band gap. A first semiconductor material (D) comprising a single material overlies the channel material (135, 136). The first semiconductor material (D) is in an uppermost portion of the channel (121). Fig. 4C, 4D, 10A, 10B, 12A, and 12B of Seo show that the first semiconductor material (D) and the inner oxide material (TL) are in the cylindrical channel/hole (121) and are both cylindrically shaped with the inner oxide material (TL) surrounding the semiconductor material (D). Therefore the first semiconductor material (D) continuously extends between opposing sidewalls of the inner oxide material (TL). Seo discloses that the first semiconductor material (D) is polysilicon (p. 8, paragraph 105). Yamazaki discloses that polysilicon has a band gap of 1.1 eV (column 6, lines 19-23). Seo does not disclose that the channel material (135, 136) is made of a material with a greater band gap than the first semiconductor material (D) which is made of polysilicon. However Shin discloses the known use of amorphous silicon as a channel material (p. 3, paragraph 56). Yamazaki further discloses that amorphous silicon has a band gap of 1.8 eV (column 6, lines 19-23). The applicant is reminded in this regard that it has been held that the selection of a known material based on its suitability for its intended use would be entirely obvious. See Sinclair & Carroll Co. v. Interchemical Corp., 325 U.S. 327, 65 USPQ 297 (1945) ("Reading a list and selecting a known compound to meet known requirements is no more ingenious than selecting the last piece to put in the last opening in a jig-saw puzzle." 325 U.S. at 335, 65 USPQ at 301.). See also In re Leshin, 277 F.2d 197, 125 USPQ 416 (CCPA 1960) (selection of a known plastic to make a container of a type made of plastics prior to the invention was held to be obvious). See MPEP 2144.07. In view of the above, it would therefore be obvious to use amorphous silicon for the channel material in the Seo device. Therefore in the device of Seo constructed in view of Shin, the first semiconductor material (D – fig. 1-13D of Seo) has a smaller band gap than the channel material (135, 136 – fig. 1-13D of Seo) made of amorphous silicon.
Fig. 1-13D of Seo discloses a second semiconductor material (132) underlying the channel material (135, 136). Seo discloses that the second semiconductor material (132) is made of silicon (p. 7, paragraph 83). Seo does not explicitly state that the second semiconductor material, which forms the channel for a transistor in conjunction with gate electrode (G1), is single crystal silicon. However Kim discloses that single crystal silicon is a known channel material for transistors (p. 1, paragraph 4). The applicant is reminded in this regard that it has been held that the selection of a known material based on its suitability for its intended use would be entirely obvious. See Sinclair & Carroll Co. v. Interchemical Corp., 325 U.S. 327, 65 USPQ 297 (1945) ("Reading a list and selecting a known compound to meet known requirements is no more ingenious than selecting the last piece to put in the last opening in a jig-saw puzzle." 325 U.S. at 335, 65 USPQ at 301.). See also In re Leshin, 277 F.2d 197, 125 USPQ 416 (CCPA 1960) (selection of a known plastic to make a container of a type made of plastics prior to the invention was held to be obvious). See MPEP 2144.07. In view of the above, it would therefore be obvious to use single crystal silicon for the second semiconductor/channel material (132) in the Seo device. Lin discloses that the band gap of single crystal silicon is approximately 1.1 eV (p. 1, paragraph 4). Therefore the second semiconductor material (132 – fig. 1-13D of Seo) has a third band gap (1.1 eV) which is substantially similar to the second band gap (1.1 eV) of the first semiconductor material (D – fig. 1-13D of Seo).
Fig. 1-13D of Seo shows a data line (128, 164, BL) that overlies the first semiconductor material (D) and is in direct contact with it. The data line (128, 164, BL - fig. 1-13D of Seo) is made of three distinct pieces. Seo does not disclose that the data line (128, 164, BL) is made of a single continuous structure. The examiner would like to note that such an issue (i.e., the integration of multiple pieces into one piece or conversely, using multiple pieces in replacing a single piece) has been previously decided by the courts:
In Howard v. Detroit Stove Works, 150 U.S. 164 (1893), the Court held, "it involves no invention to cast in one piece an article which has formerly been cast in two pieces and put together...."
Also in In re Larson, 144 USPQ 347 (CCPA 1965), the term "integral" did not define over a multi-piece structure secured as a single unit. More importantly, the court went further and stated, "we are inclined to agree with the solicitor that the use of a one-piece construction instead of the [multi-piece] structure disclosed in Tuttle et al. would be merely a matter of obvious engineering choice" (bracketed material added). The court cited In re Fridolph for support.
In re Fridolph, 135 USPQ 319 (CCPA 1962), deals with submitted affidavits relating to this issue. The underlying issue in In re Fridolph was related to the end result of making a multi-piece structure into a one-piece structure. Generally, favorable patentable weight was accorded if the one-piece structure yielded results not expected from the modification of the two-piece structure into a single piece structure.
Therefore, it would have been obvious to one of ordinary skill in the art to integrally form the data line (128, 164, BL) so that is made of a single continuous structure since it is "merely a matter of obvious engineering choice" as set forth in the above case law.
With regard to claim 2, fig. 1-13D of Seo discloses a dielectric material (139) extends vertically through the channel (121) and is adjacent to the channel material (135, 136).
In reference to claim 3, fig. 1-13D of Seo shows that the dielectric material (139) is centrally located within the channel material (135, 136).
With regard to claim 4, the device of Seo constructed in view of Shin, the channel material (135, 136 – fig. 1-13D of Seo) made of amorphous silicon has a band gap of 1.8 eV while the first semiconductor material (D – fig. 1-13D of Seo) made of polysilicon has a band gap of 1.1 eV which are values inside the applicant’s claimed ranges.
With regard to claim 5, an outer sidewall of the first semiconductor material (D – fig. 1-13D of Seo) is substantially aligned with an outer sidewall of the data line (128 – fig. 1-13D of Seo).
In reference to claim 7, there is another dielectric material (note unlabeled insulating layer directly above and in contact with G6 – fig. 1-13D of Seo) laterally adjacent to the data line (128 – fig. 1-13D of Seo).
Claim 6 is rejected under 35 U.S.C. 103 as being unpatentable over Seo as further evidenced by Yamazaki in view of Shin and further in view of Kim and as further evidenced by Lin as applied to claim 1 above and further in view of Noda et al. (USPN 5,724,297, hereinafter “Noda”).
In reference to claim 6, Seo discloses that the first semiconductor material (D or drain – fig. 1-13D) is doped with an n-type material (p. 8, paragraph 105). Seo does not disclose that the channel material (135, 136) is also doped with an n-type dopant. However figure 16B of Noda discloses counter-doping a channel such that the channel contains a dopant with the same conductivity type as the source and drain regions. Noda discloses that this lowers the threshold voltage (column 23, lines 14-25) which is desirable in the art (column 1, lines 6-26). In view of Noda, it would therefore be obvious to dope the channel material (135, 136 – fig. 1-13D of Seo) with an n-type dopant. Therefore claim 6 is not patentable over Seo, Yamazaki, Shin, Kim, Lin, and Noda.
Claim 8 is rejected under 35 U.S.C. 103 as being unpatentable over Seo as further evidenced by Yamazaki in view of Shin and further in view of Kim and as further evidenced by Lin as applied to claim 1 above and further in view of Morosawa (United States Patent Application Publication No. US 2002/0033485 A1, hereinafter “Morosawa”).
In reference to claim 8, Seo does not disclose that the first semiconductor material (D or drain – fig. 1-13D of Seo) comprises germanium or silicon germanium. However Morosawa discloses the known use of silicon germanium as a drain region material (p. 8, paragraph 88). The applicant is reminded in this regard that it has been held that the selection of a known material based on its suitability for its intended use would be entirely obvious. See Sinclair & Carroll Co. v. Interchemical Corp., 325 U.S. 327, 65 USPQ 297 (1945) ("Reading a list and selecting a known compound to meet known requirements is no more ingenious than selecting the last piece to put in the last opening in a jig-saw puzzle." 325 U.S. at 335, 65 USPQ at 301.). See also In re Leshin, 277 F.2d 197, 125 USPQ 416 (CCPA 1960) (selection of a known plastic to make a container of a type made of plastics prior to the invention was held to be obvious). See MPEP 2144.07. In view of the above, it would therefore be obvious to use silicon germanium as the material for the first semiconductor material/drain (D or drain – fig. 1-13D of Seo) overlying the channel material (135, 136 – fig. 1-13D of Seo) in the Seo device constructed in view of Shin. Therefore claim 8 is not patentable over Seo, Yamazaki, Shin, Kim, Lin, and Morosawa.
Allowable Subject Matter
Claims 11-14, 17-20, and 22 were allowed in previous Office actions.
Claim 21 is objected to as being dependent upon a rejected base claim, but would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims.
The following is a statement of reasons for the indication of allowable subject matter: the examiner is unaware of any prior art which suggests or renders obvious an apparatus comprising a channel vertically extending through a stack comprising alternating conductive structures and insulative structures, an outer oxide material extending vertically through the channel and laterally adjacent to opposing sidewalls of the channel, a nitride material extending vertically through the channel and laterally adjacent to the outer oxide material, an inner oxide material extending vertically through the channel and laterally adjacent to the nitride material, a channel material extending vertically through the channel and laterally adjacent to the inner oxide material such that the channel material exhibits a first band gap, a first semiconductor material comprising a single material overlying the channel material that exhibits a second band gap that is relatively smaller than the first band gap and is in an uppermost portion of the channel such that it vertically overlaps an uppermost conductive structure of the stack and continuously extends between opposing sidewalls of the inner oxide material, a second semiconductor material underlying the channel material which exhibits a third band gap that is substantially similar to the second band gap, and a data line overlying the first semiconductor material such that the data line comprises a single material in direct contact with the first semiconductor material as described by the applicant in claim 21. The reasons for the allowability for claims 11-14, 17-20, and 22 were discussed in previous Office actions.
Response to Arguments
Applicant's arguments filed November 24, 2025 have been fully considered but they are not persuasive. The applicant argues (p. 7 of the response) that the channel material (134, 136) or the pillars (130) and the drain regions (D) are the same material and points out a portion of Seo (p. 4, paragraph 55) to support this argument. However Seo also states (p. 8, paragraph 105) that upper parts of the active pillar (130) are removed and replaced with a conductive pattern (128) in the form of polysilicon to form the drain regions (D). Thus in Seo, the first semiconductor material (D) made of polysilicon is different from the second semiconductor material (132) made of silicon (p. 7, paragraph 83). Therefore the examiner does not find this argument to be persuasive.
The applicant also argues that the drain regions (D) are not “continuously extending” between opposing sidewalls of the inner oxide material (p. 8 of the response) since they are pierced by the filling insulation layer (139). However the examiner considers the limitation, “continuously extending,” to be overly broad and open to many interpretations. As noted in the previous Office action and in the above rejection, the first semiconductor material (D) and the inner oxide material (TL) are in the cylindrical channel/hole (121) and are both cylindrically shaped with the inner oxide material (TL) surrounding the semiconductor material (D). Therefore the first semiconductor material (D) continuously extends between opposing sidewalls of the inner oxide material (TL). Thus the examiner does not consider the broad limitation, “continuously extending,” to patentably distinguish claim 1 from the combination of Seo, Shin, and Kim.
The applicant also argues (p. 9 of the response) that the choice of amorphous silicon and single crystal silicon as channel materials is based on the applicant’s disclosure since the applicant’s intended use, that is to have different band gaps, is novel and inventive. As noted in the previous Office action and the above rejection, amorphous silicon and single crystal silicon are well known in the semiconductor art for their intended use as channel materials in transistors; at no point did the examiner argue that the intended use of amorphous silicon and single crystal silicon was for differing band gaps. Although the applicant has chosen channel materials based on differing band gaps, the fact that the applicant/inventor has recognized another advantage which would flow naturally from following the suggestion of the prior art cannot be the basis for patentability when the differences would otherwise be obvious. See Ex parte Obiaya, 227 USPQ 58, 60 (Bd. Pat. App. & Inter. 1985). Thus the examiner does not find this argument to be persuasive.
Therefore the examiner maintains the rejection of claims 1-5 and 7 are rejected under 35 U.S.C. 103 as being unpatentable over Seo as further evidenced by Yamazaki in view of Shin and further in view of Kim as further evidenced by Lin. Furthermore the examiner also maintains the rejection of claim 6 is under 35 U.S.C. 103 as being unpatentable over Seo as further evidenced by Yamazaki in view of Shin and further in view of Kim and as further evidenced by Lin as applied to claim 1 above and further in view of Noda. The examiner also maintains the rejection of claim 8 under 35 U.S.C. 103 as being unpatentable over Seo as further evidenced by Yamazaki in view of Shin and further in view of Kim and as further evidenced by Lin as applied to claim 1 above and further in view of Morosawa.
Conclusion
THIS ACTION IS MADE FINAL. Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to KEVIN QUINTO whose telephone number is (571)272-1920. The examiner can normally be reached Monday-Friday, 9-5:30.
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/KEVIN QUINTO/Examiner, Art Unit 2893
/Britt Hanley/Supervisory Patent Examiner, Art Unit 2893