Patent ID: 9520346
Filing Date: 2016-12-13
CPC Classification: H01L

Claim Text:
1. A power semiconductor module, comprising: a semiconductor chip; a buffer coupled to the semiconductor chip; and a lead frame coupled to a lower portion of the buffer, wherein the buffer comprises a plate shape and is formed of copper, and an upper surface of the buffer is bonded onto a bottom surface of the semiconductor chip by an upper solder, wherein the lead frame comprises a plate shape and is formed of copper, and an upper surface of the lead frame is bonded onto a bottom surface of the buffer by a lower solder, and wherein the upper solder comprises a mixture of 3.0 to 7.0% by weight of tin and 93.0 to 97.0% by weight of antimony, and the lower solder comprises a mixture of 94.5 to 97.0% by weight of tin, 2.5 to 4.5% by weight of silver, and 0.5 to 1.0% by weight of copper.