US 12,068,220 B2
Interface interconnect structure for efficient heat dissipation of power electronic device and preparation method therefor
Mingliang Huang, Dalian (CN); Lin Zhu, Dalian (CN); Jing Ren, Dalian (CN); and Feifei Huang, Dalian (CN)
Assigned to Dalian University of Technology, Dalian (CN)
Filed by Dalian University of Technology, Dalian (CN)
Filed on Aug. 29, 2023, as Appl. No. 18/457,904.
Prior Publication US 2024/0145336 A1, May 2, 2024
Int. Cl. H01L 23/373 (2006.01); H01L 21/48 (2006.01); H01L 23/00 (2006.01)
CPC H01L 23/3735 (2013.01) [H01L 21/4871 (2013.01); H01L 23/3733 (2013.01); H01L 24/32 (2013.01); H01L 2224/32245 (2013.01); H01L 2924/13055 (2013.01); H01L 2924/13091 (2013.01)] 15 Claims
OG exemplary drawing
 
1. An interface interconnect structure for efficient heat dissipation of a power electronic device, wherein the interface interconnect structure comprises:
a first low temperature solder layer and a second low temperature solder layer; a metal-foam metal composite material is placed between the first low temperature solder layer and the second low temperature solder layer; the first low temperature solder layer is located between an upper substrate and the metal-foam metal composite material; the second low temperature solder layer is located between the metal-foam metal composite material and a lower substrate; the first low temperature solder layer and the second low temperature solder layer have a preset thickness; the first low temperature solder layer and the second low temperature solder layer are a low temperature solder preformed sheet, and a fluxing agent is coated at both sides of the low temperature preformed sheet; the metal-foam metal composite material comprises a high-melting high-thermal-conductive porous metal and a medium-high temperature lead-free solder, and has a preset thickness, a preset thermal conductivity, and a preset coefficient of thermal expansion (CTE); a ratio of the high-melting high-thermal-conductive porous metal to the medium-high temperature lead-free solder in the metal-foam metal composite material is adjusted such that the interface interconnect structure has a thermal conductivity of 60-250 W/m·K and a CTE of 12-25 ppm/° C.; a remelting temperature of the interface interconnect structure is adjusted to a preset value by selecting metal-foam metal composite materials with different physical and chemical properties as well as first low temperature solder layers and second low temperature solder layers that each have different physical and chemical properties; in a process of reflow soldering and subsequent service, melting point depressant elements in the first low temperature solder layer and the second low temperature solder layer are subjected to bidirectional diffusion with the medium-high temperature lead-free solder in the metal-foam metal composite material such that the remelting temperature of the interface interconnect structure is greater than melting points of the first low temperature solder layer and the second low temperature solder layer, and less than a melting point of the medium-high temperature lead-free solder in the metal-foam metal composite material, to achieve low temperature soldering and high temperature service.