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 § 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.
Claim 1, 8 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 1 recites that “a second gallium arsenide layer including (j - 1) gallium arsenide monolayers” and that “j, m, and n are each an integer of 1 or more”, thus if j is 1, in this case it means j-1 is 0, thus 0 means no layer, thus it is assumed in claim 1 that if j is 1 then second gallium arsenide layer doesn’t exist, and claim 8 does not say that j is not 1, thus even in claim 8 if j is 1 then second gallium arsenide layer doesn’t exist for claim purposes. Similarly claim 8 recites “wherein the first gallium arsenide layer, the second gallium arsenide layer, and the third gallium arsenide layer each have a thickness of 0.2 nm to 1.5 nm”, however according to parent claim 1, the thickness of second gallium arsenide layer has to be 1 monolayer less than the thickness of the first gallium arsenide layer, and yet claim 8 states that the range of thickness is the same for both first gallium arsenide layer and second gallium arsenide layer, which is not clear, thus it is assumed that even in claim 8 if j is 1 then second gallium arsenide layer doesn’t exist for claim purposes. The Examiner recommends setting a different thickness range for second gallium arsenide layer, provided the Specification supports this, otherwise it may become new matter.
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.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
Note: The Examiner notes that for all the claims broadest reasonable interpretation of material such as “GaAs” means that it comprises Ga and As and similarly for other compounds.
Claim(s) 1-10 is/are rejected under 35 U.S.C. 103 as being unpatentable over Jewell et al. (US 5719895 A) hereafter referred to as Jewell in view of Svensson et al. (US 20080179589 A1) hereafter referred to as Svensson . Lee et al. (US 20130002141 A1) hereafter referred to as Lee is provided as evidence.
In regard to claim 1 Jewell teaches a [see Fig. 8 see column 32, “Semiconductor structure 50 illustrates the use of superlattice layers” see Background column 1 line 26, see column 6 “The present invention relates generally to semiconductor light sources such as LEDs and VCSELs” “It is therefore an object of the present invention to provide an active region having a quantum well structure which may be utilized in lasers” “Layers 54 and 70 may be of the same material or may be constructed of different semiconductor material or they may have the same basic composition but be of opposite conductivity types”] semiconductor superlattice structure comprising:
a first semiconductor layer [54 “confining layer 54 is grown on substrate 52 by an epitaxial process”] of a first conductivity type;
a second semiconductor layer [“a confining layer 70 is grown by an epitaxial process” “Layers 54 and 70 may be of the same material or may be constructed of different semiconductor material or they may have the same basic composition but be of opposite conductivity types”] of a second conductivity type; and
an optical absorption layer [“strain compensated superlattice”, inherently it is an absorption layer] disposed between the first semiconductor layer and the second semiconductor layer in a first direction,
wherein the optical absorption layer includes a plurality [“In this example, a multiple quantum well structure is illustrated as may be seen from second quantum well 66. It should be appreciated that quantum well 66 need not be present and that a functional device contemplated by the invention may have only one quantum well. The advantage of having multiple quantum wells is that for a given electron-hole density, the optical gain is increased. For convenience, quantum well 66 is constructed in a similar manner as quantum well 58”] of unit structures stacked in the first direction,
each of the plurality of unit structures includes a laminate and a gallium arsenide antimonide layer [“When present, tensile strained layers 56, 64, and/or 68 preferably comprise GaAs.sub.1-z P.sub.z with 0.ltoreq.z.ltoreq.1.0, if substrate 52 comprises GaAs, or In.sub.y Ga.sub.1-y As with 0.53.ltoreq.y.ltoreq.1.0 if substrate 52 comprises InP” “result of these similarites means that from a materials standpoint, In and Sb may be "interchanged" nearly equally. For example, the alloys In.sub.0.5 Ga.sub.0.5 As and In.sub.0.4 Ga.sub.0.6 As.sub.0.9 Sb.sub.0.1 are expected to be roughly equivalent in terms of lattice constant and in peak transition energy. Since the InGaAs line lies below the GaAsSb line, InGaAs has a lower peak transition energy than does GaAsSb having the same lattice constant. Therefore, from a strain-bandgap viewpoint, InGaAs is slightly preferred over GaAsSb for long-wavelength emission on GaAs substrates. InGaAs is also preferred due to more chemical characteristics. Despite the preference for InGaAs, the present invention includes the use of Sb-containing compounds. In the context of this application, statements regarding In.sub.y Ga.sub.1-y As where y is .gtoreq.0.5 re ment to include In.sub.y Ga.sub.1-y As.sub.1-w Sb.sub.w with (y+w).gtoreq.0.5” “While we have focused the discussion of the variation of In concentration, it should be appreciated that other group III semiconductor materials may be utilized. For example, the In concentration may be reduced if sufficient Sb is introduced. Nominally, each percent of Sb is almost as effective as In at reducing peak transition energy and it increases the lattice constant by about the same amount”],
the laminate includes
a first gallium arsenide layer [“GaAs(N) layer 60 having a thickness of .about.3 .ANG., i.e., one monolayer” “It is to be appreciated that the possible inclusion of nitrogen in GaAs(N) layers 60 may not perform a critical function. Rather, it may simplify the process to keep the nitrogen flowing throughout the growth of superlattice quantum well 58 due to the extreme thinness of layers 60 and 62” , see the claim states that j can be 1] including j gallium arsenide monolayers,
a first indium arsenide layer [“InAs(N) layer 62 having a thickness of .about.6 .ANG., i.e., two monolayers in this example”, in this case m is 2] including m indium arsenide monolayers,
k stacked structures [see that 58 comprises 60 at both ends and in the middle with 62 in between “Thus, one period of the superlattice structure 58 is formed. This process is repeated. FIG. 8 illustrates three periods which terminated in a GaAs(N) layer 60. This is merely illustrative of one superlattice structure which closely resembles the superlattice illustrated in FIG. 4a. For other superlattice structures, please refer to FIGS. 4a through 4d”, thus see below k “integer of 0 or more” is satisfied], each of the k stacked structures includes a third gallium arsenide layer [“GaAs(N) layer 60 having a thickness of .about.3 .ANG., i.e., one monolayer” so in this case n is 1] including n gallium arsenide monolayers and a second indium arsenide layer [“InAs(N) layer 62 having a thickness of .about.6 .ANG., i.e., two monolayers in this example”, in this case m is 2] including m indium arsenide monolayers, and
a second gallium arsenide layer [see the claim states that j can be 1, in this case it means j-1 is 0, thus 0 means no layer is claimed, not that no layer exists] including (j - 1) gallium arsenide monolayers,
the second gallium arsenide layer, the k stacked structures, the first indium arsenide layer, and the first gallium arsenide layer are stacked in this order in the first direction,
and in each of the k stacked structures, the second indium arsenide layer and the third gallium arsenide layer are stacked [see that 58 comprises 60 at both ends and in the middle with 62 in between] in this order in the first direction, and
j [see above in this case j is 1], m [see above in this case m is 2], and n [see above in this case n is 1] are each an integer of 1 or more, and k [see above k is satisfied] is an integer of 0 or more,
but does not state that the semiconductor superlattice structure is a photodetector and that the first semiconductor layer and second semiconductor layer are group III-V .
The Examiner notes that a person of ordinary skill in the art is aware that a structure designed for use in an LED can also be used for detection, see as evidence Lee paragraph 0013 “A reverse biased LED can act as a photodiode”.
See also that 54 and 70 are grown by epitaxy on group III-V and are confining.
See Svensson Fig. 1, Fig. 2 see “the detector material structure of FIG. 1 can be constructed with an intentionally undoped superlattice (such as 24 .ANG. InAs/24 .ANG. GaSb, however this is a nonlimiting example) with a p-doped GaSb bottom contact and a pseudomorphic n-doped InAs top contact layer”.
Thus, it 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 to modify Jewell to include that the semiconductor superlattice structure is a photodetector and that the first semiconductor layer and second semiconductor layer are group III-V .
Thus it would be obvious to combine the references to arrive at the claimed invention.
The motivation is that group III-V layers to contact a group III-V superlattice are known to give good results for conductivity and detection.
In regard to claim 2 Jewell and Svensson as combined teaches further comprising an indium phosphide substrate [“Device 50 is grown on a GaAs substrate 52. It should be appreciated that the substrate may also be InP as discussed below” “When present, tensile strained layers 56, 64, and/or 68 preferably comprise GaAs.sub.1-z P.sub.z with 0.ltoreq.z.ltoreq.1.0, if substrate 52 comprises GaAs, or In.sub.y Ga.sub.1-y As with 0.53.ltoreq.y.ltoreq.1.0 if substrate 52 comprises InP”], wherein the first group III-V semiconductor layer [i.e. 54 see Fig. 8] is disposed between [see Fig. 8] the indium phosphide substrate and the optical absorption layer in the first direction,
but does not state and 0.95 < y + r < 1.05 is satisfied, where y is an arsenic fraction in the gallium arsenide antimonide layer, and r is a ratio of the number of gallium arsenide monolayers to a sum of the number of gallium arsenide monolayers and the number of indium arsenide monolayers in the laminate.
See that for the example in claim 1, “GaAs(N) layer 60 having a thickness of .about.3 .ANG., i.e., one monolayer” “InAs(N) layer 62 having a thickness of .about.6 .ANG., i.e., two monolayers in this example”, thus r = 0.33, and the description for antimony, see “When present, tensile strained layers 56, 64, and/or 68 preferably comprise GaAs.sub.1-z P.sub.z with 0.ltoreq.z.ltoreq.1.0, if substrate 52 comprises GaAs, or In.sub.y Ga.sub.1-y As with 0.53.ltoreq.y.ltoreq.1.0 if substrate 52 comprises InP” “result of these similarites means that from a materials standpoint, In and Sb may be "interchanged" nearly equally. For example, the alloys In.sub.0.5 Ga.sub.0.5 As and In.sub.0.4 Ga.sub.0.6 As.sub.0.9 Sb.sub.0.1 are expected to be roughly equivalent in terms of lattice constant and in peak transition energy. Since the InGaAs line lies below the GaAsSb line, InGaAs has a lower peak transition energy than does GaAsSb having the same lattice constant. Therefore, from a strain-bandgap viewpoint, InGaAs is slightly preferred over GaAsSb for long-wavelength emission on GaAs substrates. InGaAs is also preferred due to more chemical characteristics. Despite the preference for InGaAs, the present invention includes the use of Sb-containing compounds. In the context of this application, statements regarding In.sub.y Ga.sub.1-y As where y is .gtoreq.0.5 re ment to include In.sub.y Ga.sub.1-y As.sub.1-w Sb.sub.w with (y+w).gtoreq.0.5” “While we have focused the discussion of the variation of In concentration, it should be appreciated that other group III semiconductor materials may be utilized. For example, the In concentration may be reduced if sufficient Sb is introduced. Nominally, each percent of Sb is almost as effective as In at reducing peak transition energy and it increases the lattice constant by about the same amount”, thus Jewell teaches a large range for arsenic fraction.
It 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 to use “and 0.95 < y + r < 1.05 is satisfied, where y is an arsenic fraction in the gallium arsenide antimonide layer, and r is a ratio of the number of gallium arsenide monolayers to a sum of the number of gallium arsenide monolayers and the number of indium arsenide monolayers in the laminate ”, since it has been held that where the general conditions of a claim are disclosed in the prior art, discovering the optimum or working ranges involves only routine skill in the art. In re Aller, 105 USPQ 233
In regard to claim 3 Jewell and Svensson as combined teaches [see claim 1 above, in this case j is 1, in this case m is 2, in this case n is 1] wherein j, m, and n are each 6 or less.
In regard to claim 4 Jewell and Svensson as combined teaches [see claim 1 above, see Fig. 8 see “FIG. 8 illustrates three periods which terminated in a GaAs(N) layer 60. This is merely illustrative of one superlattice structure which closely resembles the superlattice illustrated in FIG. 4a”] wherein k is 1 or more.
In regard to claim 5 Jewell and Svensson as combined teaches [see claim 1 above, see Fig. 8 see “FIG. 8 illustrates three periods which terminated in a GaAs(N) layer 60. This is merely illustrative of one superlattice structure which closely resembles the superlattice illustrated in FIG. 4a”] wherein k is 13 or less.
In regard to claim 6 Jewell and Svensson as combined teaches wherein [“When present, tensile strained layers 56, 64, and/or 68 preferably comprise GaAs.sub.1-z P.sub.z with 0.ltoreq.z.ltoreq.1.0, if substrate 52 comprises GaAs, or In.sub.y Ga.sub.1-y As with 0.53.ltoreq.y.ltoreq.1.0 if substrate 52 comprises InP” “result of these similarites means that from a materials standpoint, In and Sb may be "interchanged" nearly equally. For example, the alloys In.sub.0.5 Ga.sub.0.5 As and In.sub.0.4 Ga.sub.0.6 As.sub.0.9 Sb.sub.0.1 are expected to be roughly equivalent in terms of lattice constant and in peak transition energy. Since the InGaAs line lies below the GaAsSb line, InGaAs has a lower peak transition energy than does GaAsSb having the same lattice constant. Therefore, from a strain-bandgap viewpoint, InGaAs is slightly preferred over GaAsSb for long-wavelength emission on GaAs substrates. InGaAs is also preferred due to more chemical characteristics. Despite the preference for InGaAs, the present invention includes the use of Sb-containing compounds. In the context of this application, statements regarding In.sub.y Ga.sub.1-y As where y is .gtoreq.0.5 re ment to include In.sub.y Ga.sub.1-y As.sub.1-w Sb.sub.w with (y+w).gtoreq.0.5” “While we have focused the discussion of the variation of In concentration, it should be appreciated that other group III semiconductor materials may be utilized. For example, the In concentration may be reduced if sufficient Sb is introduced. Nominally, each percent of Sb is almost as effective as In at reducing peak transition energy and it increases the lattice constant by about the same amount”, see that Jewell discloses any portion of As can be replaced by Sb for obtaining the same results] the gallium arsenide antimonide layer has an arsenic fraction of 0.3 to 0.7.
In regard to claim 7 Jewell and Svensson as combined teaches wherein the gallium arsenide antimonide layer includes [“tensile strained layer 56 may be grown by an epitaxial process such as MBE, MOCVD or MOMBE at a temperature of 500.degree. C. for a period of 0.3 minutes. This results in tensile strained layer 56 having a thickness of 50 .ANG.”, see similarly 64, and/or 68, see that 50 angstrom of monolayers satisfies the claim limitation, since each monolayer is on the order of ~3 angstrom] p gallium arsenide antimonide monolayers, and p is an integer of 10 to 26.
In regard to claim 8 [see 112 rejection] Jewell and Svensson as combined teaches wherein the first gallium arsenide layer, the second gallium arsenide layer, and the third gallium arsenide layer each [“GaAs(N) layer 60 having a thickness of .about.3 .ANG., i.e., one monolayer”, however see claim 1, if j is 1 then j-1 is 0, thus 0 means no layer is claimed, not that no layer exists ] have a thickness of 0.2 nm to 1.5 nm.
In regard to claim 8 [see 112 rejection, this second rejection is for the case when the second gallium arsenide layer has non-zero monolayers] Jewell and Svensson as combined teaches wherein the first gallium arsenide layer, and the third gallium arsenide layer each [“GaAs(N) layer 60 having a thickness of .about.3 .ANG., i.e., one monolayer”, however see claim 1, if j is 1 then j-1 is 0, thus 0 means no layer is claimed, not that no layer exists ] have a thickness of 0.2 nm to 1.5 nm, but does not disclose second gallium arsenide layer to be 1 monolayer lower than the first, because if the the second gallium arsenide layer is chosen to be the lowermost “GaAs(N) layer 60” then it too has a 1 monolayer thickness.
However, see the claim language see “including” (j-1) means “at least” (j-1) under broadest reasonable interpretation, see Jewell teaches “One superlattice form may be a periodic structure with each period comprising three monolayers of InAs and one monolayer of GaAs. Alternatively, each period may comprise two monolayers of InAs and two monolayers of In.sub.0.5 Ga.sub.0.5 As” see that 60 comprising InGaAs is GaAs under broadest reasonable interpretation.
Thus, it 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 to modify the example of Jewell Fig. 8 to include two monolayers in 60 i.e. to modify Jewell to include wherein the first gallium arsenide layer, the second gallium arsenide layer, and the third gallium arsenide layer each have a thickness of 0.2 nm to 1.5 nm
Thus it would be obvious to combine the references to arrive at the claimed invention.
The motivation is that these are equivalent stuctures known to give good results as superlattice at chosen band gap energy.
In regard to claim 9 Jewell and Svensson as combined teaches wherein the first indium arsenide layer and the second indium arsenide layer each have [“InAs(N) layer 62 having a thickness of .about.6 .ANG., i.e., two monolayers in this example”] a thickness of 0.2 nm to 1.6 nm.
In regard to claim 10 Jewell and Svensson as combined teaches wherein the gallium arsenide antimonide layer has a thickness [“tensile strained layer 56 may be grown by an epitaxial process such as MBE, MOCVD or MOMBE at a temperature of 500.degree. C. for a period of 0.3 minutes. This results in tensile strained layer 56 having a thickness of 50 .ANG.”, see similarly 64, and/or 68] of 2.5 nm to 6.3 nm.
Conclusion
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/SITARAMARAO S YECHURI/ Primary Examiner, Art Unit 2893