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 .
Priority
Receipt is acknowledged of certified copies of papers required by 37 CFR 1.55.
Information Disclosure Statement
The information disclosure statement (IDS) submitted on 07/16/2024 is being considered by the examiner.
Drawings
The drawings submitted on 07/16/2024 are being considered by the examiner.
Claim Objections
Claim 11 is objected to because of the following informalities: the claim recites a depth-to-width ratio of 10 and it is unclear to the examiner if this is a complete testament or if relative units are missing. Appropriate correction (or explanation) is required.
Claim 14 is objected to because of the following informalities: The claim limitations are listed as “a), a), b), and c)”. The examiner is curious if it should be “a), b), c), d)”. Appropriate correction is required
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.
Claims 1-20 are rejected under 35 U.S.C. 103 as being unpatentable over Roggenbauer et al. (US 20080122025 A1).
Regarding claim 1, Roggenbauer discloses a method of forming an isolation trench, the method comprising:
a) forming a trench (940) in a substrate (602+406+402 in Fig. 8) the trench (940) extending from a first surface of the substrate (top) to an interior of the substrate (602+406); ([0045], Fig. 9) and
b) forming at least two layers of different filling materials (1042 and 1242) in the trench (940) to completely fill the trench, ([0050], [0053], Fig. 10 and 12)
Roggenbauer does not explicitly disclose:
c) wherein a step coverage of each layer of filling material is better than a step
coverage of the previous layer of filling material.
However, Roggenbauer discloses:
“the insulating layer 1042 is deposited such that its thickness is no more than one half of the widths of the trenches 940.” ([0050]) and “ the conductive layer 1242 has a thickness such that the exposed surface of the conductive layer 1242 is substantially flat or undulating.” ([0053]) and therefore, leads the examiner to believe that the step coverage of the conductive layer 1242 is better than the insulating layer 1042.
Therefore, it would have been obvious to one skilled in the art before the effective filing date to use the teachings of Roggenbauer for a step coverage of each layer of filling material is better than a step coverage of the previous layer of filling material because “a combination of deep trenches with an insulating liner and a conductive structure therein can be formed and reduce the likelihood of forming a parasitic field-effect transistor along sidewalls of the deep trenches” as well as “ also be operated to filter or otherwise reduce RF or other electromagnetic noise from reaching components that are sensitive to the RF or other electromagnetic noise. The combination also helps to reduce other crosstalk issues, switching power dissipation, and reduce spacing between components.” (Roggenbauer, [0027])
Regarding claim 2, Roggenbauer discloses the method of claim 1. Roggenbauer does not explicitly disclose wherein a fluidity of each layer of filling material is greater than that of a previous layer of filling material.
However, Roggenbauer discloses the same filling materials of the present invention which leads the examiner to believe the claimed limitation is taught by the prior art.
Therefore, it would have been obvious to one skilled in the art before the effective filing date to use the teachings of Roggenbauer for similar reasons mentioned beforehand.
Regarding claim 3, Roggenbauer discloses the method of claim 1, wherein a first layer of filling material (1042) is formed to cover both side surfaces and bottom surface of the trench (940) and starting from the second layer of filling material (1242), each layer of filling material is formed to cover a surface of the previous layer of filling material. ([0050]-[0053], Fig. 10-12)
Regarding claim 4, Roggenbauer discloses the method of claim 1, wherein a first layer of filling material (1042) comprises an insulation layer. ([0050], Fig. 10)
Regarding claim 5, Roggenbauer discloses the method of claim 1, wherein when the filling material comprises two layers (1042/1242), the step of forming at least two layers of different filling materials in the trench comprises:
a) forming an insulation layer (1042) on both side surfaces and bottom surface of the trench (940) to define an internal space (1140); (Fig. 11) and
b) filling an auxiliary layer (1242) in the trench to completely fill the internal space (1140),
Roggenbauer does not explicitly disclose:
wherein a step coverage of each layer of filling material is better than a step coverage of the previous layer of filling material.
However, Roggenbauer discloses:
“the insulating layer 1042 is deposited such that its thickness is no more than one half of the widths of the trenches 940.” ([0050]) and “ the conductive layer 1242 has a thickness such that the exposed surface of the conductive layer 1242 is substantially flat or undulating.” ([0053]) and therefore, leads the examiner to believe that the step coverage of the conductive layer 1242 is better than the insulating layer 1042.
Therefore, it would have been obvious to one skilled in the art before the effective filing date to use the teachings of Roggenbauer for similar reasons mentioned beforehand.
Regarding claim 6, Roggenbauer discloses the method of claim 5, wherein the auxiliary layer (1242) comprises tungsten (per [0053]). (Fig. 12)
Regarding claim 7, Roggenbauer discloses the method of claim 5, wherein before the step of filling the auxiliary layer (1242) in the trench (940), the method further comprises etching (per [0051]) the insulation layer (1042) located on the bottom surface of the trench to expose the substrate. (Fig. 11)
Regarding claim 8, Roggenbauer discloses the method of claim 7, further comprising performing an ion implantation process (per [0042]) on the exposed substrate (402) to form a doped region (1142) in the substrate. (Fig. 11)
Regarding claim 9, Roggenbauer discloses the method of claim 7, wherein when the auxiliary layer (1242) comprises a conductive material (per [0053]), and the auxiliary layer (1242) is connected to a reference voltage to support the substrate being externally connected. ([0023], Fig. 18-19)
Regarding claim 10, Roggenbauer discloses the method of claim 5, wherein the filling the auxiliary layer (1242) comprises using a chemical vapor deposition process (per [0053]).
Regarding claim 11, Roggenbauer discloses the method of claim 1. Roggenbauer does not disclose wherein a depth to width ratio of the trench is greater than 10.
However, Roggenbauer discloses:
“the trenches 940 have depths in a range of approximately 1.1 to approximately 9 µm, and in another embodiment, the trenches 940 have widths in a range of approximately 1.1 to approximately 5 µm” in [0048].
It would have been obvious to one skilled in the art before the effective filing date to use the teachings of Roggenbauer to have a depth to width ratio of the trench is greater than 10 with routine experiment and optimization. In re Woodruff, 16 USPQ2d 1935, 1937 (Fed. Cir. 1990) so as to “reduce spacing between components.” (Roggenbauer, [0027])”
Regarding claim 12, Roggenbauer discloses the method of claim 1. Roggenbauer does not explicitly disclose wherein a depth of the trench is greater than 20um.
However, It would have been obvious to one skilled in the art before the effective filing date to use the teachings of Roggenbauer to have a depth of the trench is greater than 20um with routine experiment and optimization. In re Woodruff, 16 USPQ2d 1935, 1937 (Fed. Cir. 1990) so as to “reduce spacing between components.” (Roggenbauer, [0027])”
Regarding claim 13, Roggenbauer discloses the method of claim 1, wherein the isolation trench is applied to a device wherein the device comprises a bipolar junction transistor (BJT) (per [0045]), and a double diffused metal oxide semiconductor (DMOS) (per [0062]).
Does not disclose:
BCD (BJT-CMOS-DMOS) device
complementary metal oxide semiconductor (CMOS),
However, Roggenbauer discloses:
“ The conductive structure lies between the first component region and the second component region. In a particular embodiment, the electronic device further includes a third component region, wherein the conductive structure lies between the second component region and the third component region.” ([0087]) And “Moreover, although specific embodiments have been illustrated and described herein, it should be appreciated that any subsequent arrangement designed to achieve the same or similar purpose may be substituted for the specific embodiments shown.” ([0094]) Leading the examiner to believe any combination of devices can be used by one skilled in the art to have a BCD device including a CMOS.
Therefore, it would have been obvious to one skilled in the art before the effective filing date to use the teachings of Roggenbauer to include a CMOS since it has been held to be within the general skill of a worker in the art to select a known material on the basis of its suitability for the intended use as a matter of obvious design choice. In re Leshin, 125 USPQ 416.
Regarding claim 14, Roggenbauer discloses an isolation trench, comprising:
a) a substrate (602+406+402); ([0043], Fig. 8)
a) a trench (940) extending from a first surface (top) of the substrate (602+406+402) to an interior of the substrate; ([0045], Fig. 9)
b) at least two layers of different filling materials (1042 and 1242/1342) that are filled in the trench (940),
Roggenbauer does not explicitly disclose:
c) wherein a step coverage of each layer of filling material is better than a step
coverage of the previous layer of filling material.
However, Roggenbauer discloses:
“the insulating layer 1042 is deposited such that its thickness is no more than one half of the widths of the trenches 940.” ([0050]) and “ the conductive layer 1242 has a thickness such that the exposed surface of the conductive layer 1242 is substantially flat or undulating.” ([0053]) and therefore, leads the examiner to believe that the step coverage of the conductive layer 1242 is better than the insulating layer 1042.
Therefore, it would have been obvious to one skilled in the art before the effective filing date to use the teachings of Roggenbauer for a step coverage of each layer of filling material is better than a step coverage of the previous layer of filling material because “a combination of deep trenches with an insulating liner and a conductive structure therein can be formed and reduce the likelihood of forming a parasitic field-effect transistor along sidewalls of the deep trenches” as well as “ also be operated to filter or otherwise reduce RF or other electromagnetic noise from reaching components that are sensitive to the RF or other electromagnetic noise. The combination also helps to reduce other crosstalk issues, switching power dissipation, and reduce spacing between components.” (Roggenbauer, [0027])
Regarding claim 15, Roggenbauer discloses the isolation trench of claim 14. Roggenbauer does not explicitly disclose wherein a fluidity of each layer of filling material is greater than that of a previous layer of filling material.
However, Roggenbauer discloses the same filling materials of the present invention which leads the examiner to believe the claimed limitation is taught by the prior art.
Therefore, it would have been obvious to one skilled in the art before the effective filing date to use the teachings of Roggenbauer for similar reasons mentioned beforehand.
Regarding claim 16, Roggenbauer discloses the isolation trench of claim 14, wherein a first layer of filling material (1042) covers both side surfaces and bottom surface of the trench (940) and starting from the second layer of filling material (1242), each layer of filling material covers a surface of the previous layer of filling material. ([0050]-[0053], Fig. 10-12)
Regarding claim 17, Roggenbauer discloses the isolation trench of claim 14, wherein a first layer (1042) of filling material comprises an insulation layer ([0050, Fig. 10).
Regarding claim 18, Roggenbauer discloses the isolation trench of claim 14, wherein when the filling material comprises two layers (1042 and 1242/1342), the step of forming at least two layers of different filling materials in the trench comprises:
a) forming an insulation layer (1042) on both side surfaces and bottom surface of the trench (940) to define an internal space (1140); (Fig. 11) and
b) filling an auxiliary layer (1242) in the trench to completely fill the internal space (1140), (Fig. 12)
Roggenbauer does not explicitly disclose:
wherein a step coverage of each layer of filling material is better than a step coverage of the previous layer of filling material.
However, Roggenbauer discloses:
“the insulating layer 1042 is deposited such that its thickness is no more than one half of the widths of the trenches 940.” ([0050]) and “ the conductive layer 1242 has a thickness such that the exposed surface of the conductive layer 1242 is substantially flat or undulating.” ([0053]) and therefore, leads the examiner to believe that the step coverage of the conductive layer 1242 is better than the insulating layer 1042.
Therefore, it would have been obvious to one skilled in the art before the effective filing date to use the teachings of Roggenbauer for similar reasons mentioned beforehand.
Regarding claim 19, Roggenbauer discloses the isolation trench of claim 14, wherein when the filling material comprises two layers (1042 and 1242/1342), the at least two layers of different filling materials comprises:
a) an insulation layer (1042) provided on both side surfaces of the trench (940) to define an internal space (1140); (Fig. 11) and
b) an auxiliary layer (1242/1342) filled in the internal space (1140) and contacting the substrate (402), (Fig. 12 and 13)
and the material of the auxiliary layer (1242/1342) is configured as conductive material (per [0053]).
Roggenbauer does not explicitly disclose:
wherein a step coverage of each layer of filling material is better than a step coverage of the previous layer of filling material.
However, Roggenbauer discloses:
“the insulating layer 1042 is deposited such that its thickness is no more than one half of the widths of the trenches 940.” ([0050]) and “ the conductive layer 1242 has a thickness such that the exposed surface of the conductive layer 1242 is substantially flat or undulating.” ([0053]) and therefore, leads the examiner to believe that the step coverage of the conductive layer 1242 is better than the insulating layer 1042.
Therefore, it would have been obvious to one skilled in the art before the effective filing date to use the teachings of Roggenbauer for similar reasons mentioned beforehand.
Regarding claim 20, Roggenbauer discloses the isolation trench of claim 18, wherein the auxiliary layer (1242/1342) comprises tungsten (per [0053]).
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure. Yindeepol et al. (US 5811315) discloses similar inventive concept may be utilized in the fabrication of CMOS, BiCMOS and bipolar devices but does not disclose all the features as required by the claim.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to ASHLEY BLACKWELL whose telephone number is (703)756-1508. The examiner can normally be reached Mon-Fri 8:00-1600.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Jacob Choi can be reached at 469-295-9060. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/ASHLEY NICOLE BLACKWELL/Examiner, Art Unit 2897
/JACOB Y CHOI/Supervisory Patent Examiner, Art Unit 2897
