# US 8,541,876 B2 · Microelectronic package having direct contact heat spreader and method of manufacturing same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,541,876 B2 - Document ID: US8541876B2 - Status: Granted - Kind: B2 - Application number: 11/242,176 - Filed: 2005-09-30 - Published: 2007-04-05 - Granted: 2013-09-24 - Earliest claimed: 2005-09-30 - Assignees: Intel Corporation - Applicants: Daoqiang Lu; Chuan Hu; Gilroy J. Vandentop; Shriram Ramanathan; Rajashree Baskaran; Valery M. Dubin - Inventors: Daoqiang Lu; Chuan Hu; Gilroy J. Vandentop; Shriram Ramanathan; Rajashree Baskaran; Valery M. Dubin - Web page: https://patentgrep.com/patent/US8541876B2 ## CPC - H10W 40/255: {having a laminate or multilayered structure, e.g. direct bond copper [DBC] ceramic substrates} - H10W 70/02: of conductive package substrates serving as an interconnection, e.g. of metal plates (manufacture or treatment of leadframes H10W70/04) - H10W 72/07251: {characterised by changes in properties of the bump connectors during connecting} - H10W 72/073: {of die-attach connectors} - H10W 72/20: Bump connectors, e.g. solder bumps or copper pillars; Dummy bumps; Thermal bumps - H10W 72/877: {Bump connectors and die-attach connectors} - H10W 74/142: {the encapsulations exposing the passive side of the semiconductor body} - H10W 74/15: on active surfaces of flip-chip devices, e.g. underfills - H10W 90/724: {between a chip and a stacked insulating package substrate, interposer or RDL} - H10W 90/734: {between a chip and a stacked insulating package substrate, interposer or RDL} - H10W: GENERIC PACKAGES, INTERCONNECTIONS, CONNECTORS OR OTHER CONSTRUCTIONAL DETAILS OF DEVICES COVERED BY CLASS H10 ## Abstract A method of fabricating a microelectronic package having a direct contact heat spreader, a package formed according to the method, a die-heat spreader combination formed according to the method, and a system incorporating the package. The method comprises metallizing a backside of a microelectronic die to form a heat spreader body directly contacting and fixed to the backside of the die thus yielding a die-heat spreader combination. The package includes the die-heat spreader combination and a substrate bonded to the die. ## Claims ### Claim 1 A microelectronic package comprising: a substrate; a die having an active surface and a backside and being bonded to the substrate at the active surface thereof; an encapsulant surrounding the die and substantially planar with the backside of the die; a heat spreader body directly contacting and fixed to the backside of the die wherein the heat spreader body including one of a barrier layer and a seed layer in direct contact with the backside of the die and the encapsulant surrounding the die. ### Claim 2 (depends on 1) The package of claim 1, wherein the die comprises silicon and wherein a residual stress within the silicon at room temperature is below about 50 MPa. ### Claim 3 (depends on 1) The package of claim 1, wherein a grain boundary and grain orientation of a metal of the heat spreader body at a region of the heat spreader body adjacent the backside of the die is different from a grain boundary and grain orientation of the metal of the heat spreader body at other regions of the heat spreader body. ### Claim 4 (depends on 1) The package of claim 1, further comprising solder joints and at least one of an encapsulant and an underfill material disposed between the active surface of the die and a die-side of the substrate to bond the die to the substrate. ### Claim 5 (depends on 1) The package of claim 1, wherein the heat spreader body is made of a material comprising at least one of copper, a copper alloy, a copper laminate, a copper composite, aluminum and an aluminum alloy. ### Claim 6 (depends on 1) The package of claim 1, wherein the heat spreader body comprises a metal composite material comprising a metal and particles having a thermal conductivity above that of the metal. ### Claim 7 (depends on 1) The package of claim 1, wherein the heat spreader body includes a microchannel structure, the package further comprising a cover piece attached onto the microchannel structure. ### Claim 8 (depends on 2) The package of claim 2, further comprising a heat sink attached onto the heat spreader body with a thermal interface material. ### Claim 9 (depends on 1) The microelectronic package of claim 1 wherein said heat spreader body has a thickness between about 0.2 mm and about 3 mm. ### Claim 10 (depends on 1) The microelectronic package of claim 1 wherein said heat spreader body has a width larger than a width of said die. ### Claim 11 A die-heat spreader combination comprising: a die having an active surface and a backside; an encapsulant surrounding the die and substantially planar with the backside of the die; and a heat spreader body directly contacting and fixed to the backside of the die wherein the heat spreader body comprises a material selected from the group consisting of copper, a copper alloy, a copper laminate, a copper composite, aluminum and an aluminum alloy and wherein the heat spreader body including one of a barrier layer and a seed layer in direct contact with the backside of the die and the encapsulant surrounding the die. ### Claim 12 (depends on 11) The die-heat spreader combination of claim 11, wherein the heat spreader body includes a microchannel structure. ### Claim 13 (depends on 11) The die heat spreader combination of claim 11 wherein said heat spreader body has a width larger than a width of said die. ### Claim 14 A system comprising: a microelectronic assembly including: a microelectronic package comprising: a substrate; a die having an active surface and a backside and being bonded to the substrate at the active surface thereof; an encapsulant surrounding the die and substantially planar with the backside of the die; a heat spreader body directly contacting and fixed to the backside of the die wherein said heat spreader body has a thickness greater than about 0.2 mm and wherein the heat spreader body including one of a barrier layer and a seed layer in direct contact with the backside of the die and the encapsulant surrounding the die; and a main memory coupled to the microelectronic assembly. ### Claim 15 (depends on 14) The system of claim 14, wherein the heat spreader body is made of a material comprising at least one of copper, a copper alloy, a copper laminate, a copper composite, aluminum and an aluminum alloy. ### Claim 16 (depends on 14) The system of claim 14 wherein said heat spreader body has a thickness between about 0.2 mm and about 3 mm. ### Claim 17 (depends on 11) The die heat spreader combination of claim 11 wherein said heat spreader body has a thickness greater than about 0.2 mm. ### Claim 18 (depends on 11) The die heat spreader combination of claim 11 wherein said heat spreader body has a thickness between about 0.2 mm and about 3 mm. ### Claim 19 (depends on 14) The system of claim 14 wherein said heat spreader body has a width larger than a width of said die.