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 .
Election/Restrictions
Applicant’s election without traverse of Invention I (claims 1-9) and Species C (Fig. 5C; claims 1-9) in the reply filed on 8.4.2026 is acknowledged.
Claims 10-20 are withdrawn from further consideration pursuant to 37 CFR 1.142(b) as being drawn to a nonelected inventions/species, there being no allowable generic or linking claim. Election was made without traverse in the reply filed on 8.4.2026.
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 1 is rejected under 35 U.S.C. 103 as being unpatentable over Shih et al. (US 20110316147 A1) in view of Tsang et al. (US 20240379514 A1).
Regarding claim 1, Shih discloses a semiconductor package (Fig. 1G), comprising:
an interposer (100 minus 34/32, Fig. 1F) having an interposer bonding structure (34/32, Fig. 1F) thereon, wherein a sidewall of the interposer bonding structure is flush with a sidewall of the interposer (Fig. 1G);
a semiconductor die (44) having a die bonding structure (46A/46B) thereon, wherein a sidewall (at 46B) of the die bonding structure (46A/46B) is recessed from a sidewall of the semiconductor die (Fig. 1G), and the semiconductor die (44) is bonded to interposer (100 minus 34/32) through the die bonding structure (46A/46B) and the interposer bonding structure (34/32, Fig. 1G); and
a first
Shih fails to disclose a first polymeric material, wherein a porosity of the first polymeric material is less than about 20% in the non-bond region between the semiconductor die and the interposer.
Tsang discloses (Fig. 7) a first polymeric material (138, [0049]-“epoxy”), wherein a porosity of the first polymeric material is less than about 20% ([0049] – “void-free fluid” presumed to indicate a non-porous material) in the non-bond region (e.g., in between 136) between the semiconductor die (137) and the interposer (130).
It would have been obvious to one of ordinary skill in the art, before the effective filing date, to include the polymeric material of Tsang in Shih and arrive at the claimed invention so as to encapsulate a space between a die and an interposer without voids which would compromise mechanical strength or functionality of the underfill material.
Claim 3 is rejected under 35 U.S.C. 103 as being unpatentable over Shih et al. (US 20110316147 A1) in view of Tsang et al. (US 20240379514 A1) as applied to claim 1 above, and further in view of Huang et al. (US 20190006256 A1).
Regarding claim 3, Shih/Tsang fails to disclose the semiconductor package of claim 1, wherein the semiconductor die has a chamfer portion, and the first polymeric material covers the chamfer portion.
Huang discloses wherein the semiconductor die (101) has a chamfer portion (115), and the first polymeric material (201/501 both “epoxy” at [0036]) covers the chamfer portion (Fig. 5).
It would have been obvious to one of ordinary skill in the art, before the effective filing date, to include the chamfer arrangement of Huang in Shih/Tsang and arrive at the claimed invention so as to “prevent cracks from occurring at the corners of semiconductor dies” (Tsang, Abstract).
Claims 4 and 6 are rejected under 35 U.S.C. 103 as being unpatentable over Shih et al. (US 20110316147 A1) in view of Tsang et al. (US 20240379514 A1) as applied to claim 1 above, and further in view of Czubarow et al. (US 20150252217 A1).
Regarding claim 4, Shih/Tsang fails to disclose the semiconductor package of claim 1, wherein the first polymeric material has a maximum filler size of about 10 um or less.
Czubarow discloses wherein the first polymeric material has a maximum filler size of about 10 um or less ([0041], [0054] – “maximum particle size of the filler particles included in the underfill composition is about 2.5 to about 3 microns”).
It would have been obvious to one of ordinary skill in the art, before the effective filing date, to include the filler particle size of Czubarow in Shih/Tsang and arrive at the claimed invention so as to achieve proper fluidity characteristics in an uncured state and proper bulk thermal conductivity in a cured state (Czubarow, [0051]) and/or achieve “superior fluidity value at a bond line of about 20 microns or less and still have a superior bulk thermal conductivity in the cured state” (Czubarow, [0010]).
Regarding claim 6, Shih/Tsang fails to disclose the semiconductor package of claim 1, wherein the first polymeric material has a viscosity of less than about 10 Pa*s.
Czubarow discloses wherein the first polymeric material has a viscosity of “about 0.1 to about 150 Pas” ([0011]. Note that the disclose range overlaps with “less than about 10 Pa*s” as claimed).
It would have been obvious to one of ordinary skill in the art, before the effective filing date, to select a viscosity value which falls inside both the prior art range of Czubarow and the claimed range in Shih/Tsang and arrive at the claimed invention so as to achieve proper fluidity characteristics in an uncured state (Czubarow, [0051]) and/or achieve “superior fluidity value at a bond line of about 20 microns or less and still have a superior bulk thermal conductivity in the cured state” (Czubarow, [0010]), and/or because “In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists” per MPEP 2144.05-I.
Claims 5 and 7-9 are rejected under 35 U.S.C. 103 as being unpatentable over Shih et al. (US 20110316147 A1) in view of Tsang et al. (US 20240379514 A1) as applied to claim 1 above, and further in view of Kwon et al. (US 9627329 B1).
Regarding claim 5, Shih/Tsang fails to disclose the semiconductor package of claim 1, wherein the first polymeric material has a thixotropic index of about 1. 5 or more.
Kwon discloses the first polymeric material has a thixotropic index of “about 0.5 to about 1.5” (Note: about 0.5 to about 1.5 overlap the claimed “about 1. 5 or more” at “about 1.5).
It would have been obvious to one of ordinary skill in the art, before the effective filing date, to select a thixotropic index value of, e.g., 1.5 which falls inside both the prior art range of Kwon and the claimed range in Shih/Tsang and arrive at the claimed invention so as to allow an underfill material to move via capillary action (Kwon, “The die underfill material 310 may have a thixotropic index of between about 0.5 to about 1.5, which allows the die underfill material 310 to wick between the interposer 104 and the die 102 via capillary action”), and/or because “In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists” per MPEP 2144.05-I.
Regarding claim 7, Shih/Tsang fails to disclose the semiconductor package of claim 1, further comprising a second polymeric material disposed over the interposer, laterally encapsulating the semiconductor die and covering the first polymeric material, wherein a maximum filler size of the first polymeric material is less than a maximum filler size of the second polymeric material.
Kwon discloses further comprising a second polymeric material (112) disposed over the interposer (104), laterally encapsulating the semiconductor die (102) and covering the first polymeric material (310, Figs. 2-3), each of the first and second polymeric materials comprising fillers (“The stiffening material 112 may additionally include fillers” and “The die underfill material 310 may additionally include fillers”).
It would have been obvious to one of ordinary skill in the art, before the effective filing date, to include the second polymeric materials of Kwon in Shih/Tsang so as to reinforce the interposer (Kwon, “The interposer 104, reinforced by the stiffening material 112, is more robust and less likely to crack or become damaged from handling during the subsequent fabrication processes”).
Regarding “wherein a maximum filler size of the first polymeric material is less than a maximum filler size of the second polymeric material”, it would have been obvious to one of ordinary skill in the art, before the effective filing date, to experiment/optimize maximum filler size within both the first and second polymeric materials in the device of Shih/Tsang/Kwon and arrive at the claimed combination so as to ensure that the first polymeric material is void-free in the space between the IC and the interposer and flows via capillary action which leads to a lower maximum filler size while reinforcing the interposer with the second polymeric material having a higher filler size for said purpose.
Regarding claim 8, Shih/Tsang/Kwon fails to disclose the semiconductor package of claim 7, wherein a thixotropic index of the first polymeric material is greater than a thixotropic index of the second polymeric material.
However, it would have been obvious to one of ordinary skill in the art, before the effective filing date, to experiment/optimize said index within both the first and second polymeric materials in the device of Shih/Tsang/Kwon and arrive at the claimed combination so as to ensure that the first polymeric material is void-free in the space between the IC and the interposer, flows via capillary action and does not spill outside of the intended space which leads to a higher index.
Regarding claim 9, Shih/Tsang/Kwon fails to disclose the semiconductor package of claim 7, wherein a viscosity of the first polymeric material is less than a viscosity of the second polymeric material.
However, it would have been obvious to one of ordinary skill in the art, before the effective filing date, to experiment/optimize viscosity within both the first and second polymeric materials in the device of Shih/Tsang/Kwon and arrive at the claimed combination so as to ensure that the first polymeric material is void-free in the space between the IC and the interposer and flows via capillary action which leads to a lower viscosity.
Allowable Subject Matter
Claim 2 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: wherein a sidewall of the first polymeric material is flush with the sidewall of the semiconductor die and the sidewall of the interposer is not taught or suggested by the prior art of record.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
US 20060138643 A1 to Lu et al. discloses an underfill (108) with a sidewall flush with that of a package substrate (102, Fig. 1).
Any inquiry concerning this communication or earlier communications from the examiner should be directed to ANDRES MUNOZ whose telephone number is (571)270-3346. The examiner can normally be reached 8AM-5PM Central Time.
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/Andres Munoz/Primary Examiner, Art Unit 2818
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