	US 11,887,909 B2
	Copper/titanium/aluminum joint, insulating circuit substrate, insulating circuit substrate with heat sink, power module, LED module, and thermoelectric module
Nobuyuki Terasaki, Saitama (JP)
Assigned to MITSUBISHI MATERIALS CORPORATION, Tokyo (JP)
Appl. No. 16/959,160
Filed by MITSUBISHI MATERIALS CORPORATION, Tokyo (JP)
PCT Filed Feb. 13, 2018, PCT No. PCT/JP2018/004835 § 371(c)(1), (2) Date Jun. 30, 2020, PCT Pub. No. WO2019/159219, PCT Pub. Date Aug. 22, 2019.
Prior Publication US 2020/0343158 A1, Oct. 29, 2020
Int. Cl. H01L 23/373 (2006.01); H01L 33/64 (2010.01); H10N 10/17 (2023.01)

CPC H01L 23/3735 (2013.01) [H01L 33/641 (2013.01); H01L 33/647 (2013.01); H10N 10/17 (2023.02)]

16 Claims

1. A copper/titanium/aluminum bonded body in which a copper member made of copper or a copper alloy and an aluminum member made of aluminum having a purity of 99 mass % or more are bonded via a titanium layer,

wherein an intermetallic compound containing Cu and Ti and an intermetallic compound unformed part which is a part free of formation of the intermetallic compound are formed at a bonded interface of the copper member and the titanium layer,

a maximum value of a length L_iof the intermetallic compound unformed part along the bonded interface is 4 μm or more and 20 μm or less in the bonded interface of the copper member and the titanium layer,

a ratio ΣL_i/L₀is 0.16 or less, ΣL_ibeing a total length of the intermetallic compound unformed part along the bonded interface and of L₀being a total length of the bonded interface along the bonded interface,

the length L_iis a region between intermetallic compound phases at the bonded interface, and

the intermetallic compound phases are regions, where the Cu concentration is 5 at % or more and 84 at % or less and the Ti concentration is 16 at % or more and 70 at % or less, in a concentration distribution of Cu and Ti of a region including the bonded interface of the copper member and the titanium layer using an electron probe micro-analyzer (EPMA).