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
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
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.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
Claim(s) 1-3, 5, 6, 9-12, and 16-18 is/are rejected under 35 U.S.C. 103 as being unpatentable over Liu et al (US 2011/0143091) in view of Rudolph et al (DE 10 2008034029), an English computer translation (CT) is provided, Muhe (US 2007/0151510), Dropka et al (WO 2014/202284 A1), an English computer translation is provided, and Liu et al (US 2011/0293890).
Liu et al teaches a vertical gradient freeze system 20 for ([0016]-[0022], [0024]-[0028]); the system comprising: a crucible 27 to contain a raw melt material 32 and seed material 28 during a formation process; one or more heating elements 60 arranged in a plurality of heating zones; and a pedestal (crucible support 22) to move relative to the crucible, the system operable to control heating of the plurality of heating zones and movement of the pedestal to form a single crystal having an 8 inch diameter ingot (Fig 1A; 3B, and 4; and paragraphs [0017]-[0026] teaches vertical Bridgman apparatus wherein the crucible can be moved while precisely controlling the crucible down speed and temperature gradient). Liu et al also teaches the growth furnace may have a plurality of heating zones, such as between 4 to 8 heating zones and a controller may control one or more of the heating zones to perform a vertical gradient freeze process on the crucible, wherein the heating zones of the furnace are controlled separately and individually with regard to their respective power supplies via a computer that is programmed with temperature gradient requirements ([0041]-0050]), which clearly suggests a plurality of heating zones including an upper heating zone, a lower heating zone and a middle heating zone wherein each heating zone is enabled to heat the crucible at different temperature from each other heating zone. It is noted that Liu et al teaches 4 to 8 heating zones that are individually controlled; therefore, for a 4 zone heating system, the top zone reads on the upper zone, the middle 2 zones reads on the middle zone and the bottom zone reads on the lower heating zone; and this logic would be applicable to any system using more than 3 zones.
Liu et al teaches one or more heating elements arranged in a plurality of heating zones. Liu et al does not a plurality of heating coils arranged in a plurality of heating zones including a top heating zone above the crucible containing the GaAs liquid melt, an upper heating zone, a lower heating zone, and a middle heating zone, wherein each heating zone of the plurality of heating zones is enabled to heat the crucible at different temperatures from each other heating zone.
In a vertical gradient freeze or Bridgman method (CT [0058]), Rudolph et al teaches the system comprising: a crucible 25 containing a melt 5 and seed material during a formation process (CT [0037], [0070]-[0073]); one or more heating coils 311, 312,313, 321, 322, 323 arranged in a plurality of heating zones; and the system operable to control heating of the plurality of heating zones (CT [0044]-[0045], [0049] teaches the heat quantity, alternating field frequency and phase angle can be controlled independently of each other in the outer heater-magnet module and the inner heater-magnet module, so that the radial course of isotherms and magnetic field lines as well as the solid-liquid phase boundary in the crucibles can be adjusted and controlled during the growth process; and it is possible to control individual coil segments of the multi-coil arrangement). Rudolph et al teaches using at least two, preferably three heater coil segments 311, 312,313, 321, 322, 323 wherein the top coil is above the crucible (Fig 4; CT [0026]), and controlling the heating such that a plurality of isotherms a,b,c,d (heating zones) are formed and the distance between the isotherms is 25K each (Fig 4; CT [0073]), wherein the top heating zone (isotherm a) is above the crucible containing the melt (Fig 4), which clearly suggests a plurality of heating zones including a top heating zone a above the crucible, an upper heating zone b, a lower heating zone d, and a middle heating zone c, wherein each heating zone of the plurality of heating zones is enabled to heat the crucible at different temperatures from each other heating zone, which clearly suggests temperatures individually selected for each side heating zone.
It would have been obvious to one of ordinary skill in the art at the time of filing to modify Liu et al by using heating coils arranged in a plurality of heating zones, as taught by Rudolph et al, to control the temperature gradient to produce a desired phase boundary shape temperature gradient with small temperature gradients suitable for growth (CT [0022]).
The combination of Liu et al and Rudolph et al does not teach a plurality of heating coils arranged in a top heating zone, wherein the heating coils in the top heating zone extend vertically over and cover the crucible top and a top side of the melt contained in the crucible.
In an apparatus a vertical gradient freeze or vertical Bridgman crystal growth (abstract), Muhe teaches a furnace in which a hollow body 2 within a vessel 1 and contains a crucible 6 with a growing crystal 3, a semiconductor melt 4; a bottom heater 10 is situated beneath a core zone of the furnace, and a top heater 13 is situated above the core zone, and the core zone is surrounded by jacket heaters 11 and 12; and controlling the temperatures of the heaters such that the melt can solidify continuously from the bottom to the top (Fig 1; [0030]-[0035]), which clearly suggests the top heating a zone heat the melt axially downward through the crucible top and time side of the melt at temperatures selected for the top heating zone.
It would have been obvious to one of ordinary skill in the art at the time of filing to modify the combination of Liu et al and Rudolph et al by providing a top heater in the top heating zone extend vertically over and cover the crucible top and a top side of the melt contained in the crucible, as taught by Muhe, to heat the melt and provide a desired temperature gradient within the melt for crystal growth.
The combination of Liu et al, Rudolph et al and Muhe does not teach the top heater comprises a plurality of heating coils.
In a VGF crystallization system, Dropka et al teaches a ceiling heater arranged above a crucible, wherein the ceiling heater comprises two or more coils in the form of a circle or spiral, and different designs of the arrangement are possible and may consist of any number of coils (CT [0020]-[0025]).
It would have been obvious to one of ordinary skill in the art at the time of filing to modify the combination of Liu et al, Rudolph et al and Muhe by designing the ceiling heater comprising two or more coils, as taught by Dropka et al, to heat a crucible using a conventionally known design.
The combination of Liu et al, Rudolph et al, Muhe and Dropka et al does not teach a crucible containing a GaAs liquid melt. This limitation is a recitation of intended use. A recitation of the intended use of the claimed invention must result in a structural difference between the claimed invention and the prior art in order to patentably distinguish the claimed invention from the prior art. If the prior art structure is capable of performing the intended use, then it meets the claim. Here, the combination of Liu et al, Rudolph et al, Muhe and Dropka et al teaches a crucible for VGF/VB crystal growth; therefore, would be capable of being filled with any desired crystal material, such as GaAs.
In regards to the limitation “a vertical gradient freeze system for forming gallium arsenide (GaAs) 8 inch substrates having silicon as a dopant,” this limitation merely recites an intended use limitation and occurs in the preamble. When reading the preamble in the context of the entire claim, the recitation “a vertical gradient freeze system for forming gallium arsenide (GaAs) 8 inch substrates having silicon as a dopant” is not limiting because the body of the claim describes a complete invention and the language recited solely in the preamble does not provide any distinct definition of any of the claimed invention’s limitations. Thus, the preamble of the claim(s) is not considered a limitation and is of no significance to claim construction. See Pitney Bowes, Inc. v. Hewlett-Packard Co., 182 F.3d 1298, 1305, 51 USPQ2d 1161, 1165 (Fed. Cir. 1999). See MPEP § 2111.02. Also, a recitation of the intended use of the claimed invention must result in a structural difference between the claimed invention and the prior art in order to patentably distinguish the claimed invention from the prior art. If the prior art structure is capable of performing the intended use, then it meets the claim. Here, the combination of Liu et al, Rudolph et al, Muhe and Dropka et al teaches all of the claimed structural limitations of the apparatus, as discussed above. Adding a silicon dopant to a GaAs melt is mere intended use and system taught by combination of Liu et al, Rudolph et al, Muhe and Dropka et al is capable of being filled with a Si dopant; therefore, meets the claimed structural limitation.
Liu et al (‘091) teaches a vertical gradient freeze system 20 for ([0016]-[0022], [0024]-[0028]); the system comprising: one or more heating elements 60 arranged in a plurality of heating zones; and a pedestal (crucible support 22) to move relative to the crucible, the system operable to control heating of the plurality of heating zones and movement of the pedestal to form a single crystal having an 8 inch diameter ingot (Fig 1A; 3B, and 4; and paragraphs [0017]-[0026] teaches vertical Bridgman apparatus wherein the crucible can be moved while precisely controlling the crucible down speed and temperature gradient). The combination of Liu et al, Rudolph et al, Muhe and Dropka et al does not explicitly teach the system is configured to control the plurality of heating coils and movement of the pedestal so as to develop a concave interface between the GaAs liquid melt and the single crystal GaAs substrate that has a center that is 5-20 mm lower than an edge of the single crystal GaAs substrate.
In an method and apparatus for VGF, Liu et al (‘890) teaches to achieve the low EPD, several VGF parameters are carefully controlled, and the parameters may include the shape of the melt/crystal interface which is controlled to be concave or convex to the melt front ([0021], claim 5).
It would have been obvious to one of ordinary skill in the art at the time of filing to modify the combination of Liu et al, Rudolph et al, Muhe and Dropka et al to have a system is configured to control the plurality of heating coils and movement of the pedestal so as to develop a concave interface between the GaAs liquid melt and the single crystal GaAs substrate, as taught by Liu et al (‘890) to achieve a low EPD by controlling the VGF parameters, i.e. interface shape.
In regards to the concave interface has a center that is 5-20 mm lower than the edge of the single crystal GaAs substrate, the combination of Liu et al (‘091), Rudolph et al, Muhe, Dropka et al and Liu et al (‘890) teaches controlling the pedestal and temperature gradient using a plurality of heating coils, and controlling the shape to concave or convex by controlling the process parameters; therefore, the apparatus taught by prior art is configured to produce any desired shape, such as 5-20 mm concave interface.
Referring to claim 2, the combination of Liu et al (‘091), Rudolph et al, Muhe, Dropka et al and Liu et al (‘890) teaches an ampoule 26 supporting a crucible 27 (Liu Fig 1A; [0016]).
Referring to claim 3 and 5, the combination of Liu et al (‘091), Rudolph et al, Muhe, Dropka et al and Liu et al (‘890) teaches crucible support (pedestal) is capable of being moved downward relative to the plurality of heating coils (Liu [0019]).
Referring to claim 6, these limitations merely recite an intended use. The combination of Liu et al (‘091), Rudolph et al, Muhe, Dropka et al and Liu et al (‘890) teaches a plurality of heating zones; and one or more heating coils arranged in a plurality of heating zones; and a pedestal to move relative to the crucible (Liu [0019] teaches crucible support 22 moved during growth), the system operable to control heating of the plurality of heating zones and movement of the pedestal to form a single crystal; and control the temperature gradient to produce a desired phase boundary shape temperature gradient with small temperature gradients suitable for growth (CT [0022]) and controlling the interface shape to reduce EPD (Liu (‘890) [0021]); therefore would be capable of the claimed intended use to control a shape of an interface between the GaAs liquid melt and crystals to achieve low etch pit density.
Referring to claim 9, this merely recites an intended use of the apparatus. The combination of Liu et al (‘091), Rudolph et al, Muhe, Dropka et al and Liu et al (‘890) also teaches a vertical gradient freeze system comprising a crucible (Liu [0019]). The combination of Liu et al (‘091), Rudolph et al, Muhe, Dropka et al and Liu et al (‘890) does not teach a boron trioxide is placed as an encapsulant. This limitation is a recitation of intended use. A recitation of the intended use of the claimed invention must result in a structural difference between the claimed invention and the prior art in order to patentably distinguish the claimed invention from the prior art. If the prior art structure is capable of performing the intended use, then it meets the claim. Here, the combination of Liu et al (‘091), Rudolph et al, Muhe, Dropka et al and Liu et al (‘890) teaches a crucible for VGF/VB crystal growth; therefore, would be capable of being filled with any desired crystal material, such as a boron trioxide.
Referring to claim 10-11, the combination of Liu et al (‘091), Rudolph et al, Muhe, Dropka et al and Liu et al (‘890) teaches a heater and moving pedestal capable of the claimed cooling rate and temperature gradient. Furthermore, the combination of Liu et al (‘091), Rudolph et al, Muhe, Dropka et al and Liu et al (‘890) teaches a cooling rate of 0.1-10°C/hr and a temperature gradient of 0.5-10°C/cm (Liu [0032]-[0035). Overlapping ranges are prima facie obvious (MPEP 2144.05).
Referring to claim 12, the combination of Liu et al (‘091), Rudolph et al, Muhe, Dropka et al and Liu et al (‘890) teaches insulating material filled the support cylinder (Liu [0023]).
Referring to claim 13-18, these limitations merely recite an intended use of the apparatus. The formation of devices and substrate properties are not structural limitations of the apparatus, and merely recite the products produced from the apparatus. A recitation of the intended use of the claimed invention must result in a structural difference between the claimed invention and the prior art in order to patentably distinguish the claimed invention from the prior art. If the prior art structure is capable of performing the intended use, then it meets the claim. Here, the combination of Liu et al (‘091), Rudolph et al, Muhe, Dropka et al and Liu et al (‘890) teaches all of the claimed structural limitations of the apparatus, as discussed above; therefore, would be capable of the claimed intended use.
Claim(s) 4 is/are rejected under 35 U.S.C. 103 as being unpatentable over Liu et al (US 2011/0143091) in view of Rudolph et al (DE 10 2008034029), an English computer translation (CT) is provided, Muhe (US 2007/0151510), Dropka et al (WO 2014/202284 A1), an English computer translation is provided, and Liu et al (US 2011/0293890), as applied to claims 1-3, 5, 6, 9-12, and 16-18 above, and further in view of Shibata (JP 2010-030847), an English computer translation (CT2) is provided.
The combination of Liu et al (‘091), Rudolph et al, Muhe, Dropka et al and Liu et al (‘890) teaches all of the limitations of claim 4, as discussed above, except the pedestal is operable to rotate relative to the heating coils.
In a vertical Bridgman apparatus, Shibata teaches a crucible i; a plurality of heaters 3; a susceptor 7 mounted on a support member 8 and rotating the crucible support member (CT2 [0060]-[0073]). Shibata teaches Si doped GaAs single crystal growth using a B2O3 liquid sealant 9 (CT2 [0060]-[0073]). Shibata teaches crucible rotation improves axial symmetry of the temperature distribution in the melt and impurity concentration can be made uniform (CT2 [0055]-[0070]).
It would have been obvious to one of ordinary skill in the art at the time of filing to modify the combination of Liu et al (‘091), Rudolph et al, Muhe, Dropka et al and Liu et al (‘890) by providing a pedestal is operable to rotate relative to the heating coils, as taught by Shibata, to improve axial symmetry of the temperature distribution in the melt and improve uniformity of the impurity concentration.
Claim(s) 31 is/are rejected under 35 U.S.C. 103 as being unpatentable over Liu et al (US 2011/0143091) in view of Rudolph et al (DE 10 2008034029), an English computer translation (CT) is provided, Muhe (US 2007/0151510), Dropka et al (WO 2014/202284 A1), an English computer translation is provided, and Liu et al (US 2011/0293890), as applied to claims 1-3, 5, 6, 9-12, and 16-18 above, and further in view of Lange et al (WO 2008155137A1), an English computer translation (CT2) is provided.
The combination of Liu et al (‘091), Rudolph et al, Muhe, Dropka et al and Liu et al (‘890) teaches all of the limitations of claim 31, as discussed above, except one or more coils of the top heating zone are misaligned relative to one or more coils of the upper, middle or lower heating zones.
In a crystal growth apparatus, Lange et al teaches a crucible (3) provided with a bottom (3b), containing a melt (2), and arranged in a growing chamber (1), and a heating device (4) surrounding the crucible and embodied as a multiple-coil arrangement of coils (5), (6), (7) arranged one above the other (abstract; Fig 1, 2, 11, 12, and 13). Lange et al teaches multi-coil arrangement according to the invention takes on a shape that deviates from the usual straight cylindrical shape, wherein the top coil is misaligned with a lower coil (CT2 [0017], [0024] [0100]-[0103]; Fig 1, 2, 11, 12, and 13), which clearly suggests one or more coils of the top heating zone are misaligned relative to one or more coils of the upper, middle or lower heating zones.
It would have been obvious to one of ordinary skill in the art at the time of filing to modify the combination of Liu et al (‘091), Rudolph et al, Muhe, Dropka et al and Liu et al (‘890) by having one or more coils of the top heating zone are misaligned relative to one or more coils of the upper, middle or lower heating zones, as taught by Lange et al, to control the Lorentz force distribution (CT2 [0037]-[0040]).
Response to Arguments
Applicant’s arguments with respect to claim(s) 1-3, 5, 6, 9-12, 16-18 and 31 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
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
Kremer et al (US 4,999,082) teaches a vertical Bridgman process comprising a rotating pedestal; a temperature gradient of about 5-20°C/cm and reducing a temperature of a hot zone at a rate of 1°C/hour (col 7, ln 1-67).
Muhe (US 2007/0151510) teaches a plurality of heating zones wherein the temperatures of jacket heaters are usually regulated so that the temperatures at the individual regulation points arranged vertically one above the other coincide with the vertical temperature profile desired at the particular point in time of crystal growth ([0016]; Fig 1).
Fujikawa et al (US 5,698,029) teaches a heating zone of each of the heater elements 18, 18 are inserted into the thermocouple and depending on the temperature detected via these thermocouples 28, the supply capability to the individual heater elements 18, 18 is controlled (Fig 1-6; col 7, ln 1 to col 8, ln 50).
Mellen (US 4,086,424) teaches a dynamic gradient furnace with 21 individually controlled heating zones, wherein zones 1 to 18 are at 900°C, zones 19 and 20 at 800°C and zone 21 at 700°C (col 4,l n 1-67 and col 5, ln 1-67).
Fornari et al (DE 10 2007006731) teaches an induction heating device produces a required temperature gradient with small temperature gradients suitable for growth (CT [0015]-[0036]).
Shetty et al (US 2020/0190697) teaches to achieve low EPD, several VGF parameters are carefully controlled. The first parameter may include the shape of the melt/crystal interface 140, which may be controlled to be concave to the melt, for example, being 10 mm concave with the center being -10 mm lower than the edge of the 6″ diameter crystal. This may be controlled with different temporal and/or spatial temperature profiles ([0017]).
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). 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 MATTHEW J SONG whose telephone number is (571)272-1468. The examiner can normally be reached Monday-Friday 10AM-6PM.
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MATTHEW J. SONG
Examiner
Art Unit 1714
/MATTHEW J SONG/ Primary Examiner, Art Unit 1714