| abstract |
Provided is a lead frame capable of suppressing blackening of a sealing portion and suppressing a decrease in adhesion strength of a reflector joint portion. A lead frame 110, which is a constituent element of an optical semiconductor device 100 and has a region on a surface where a reflector 170 surrounding a transparent sealing portion 180 is disposed, and is formed in a multilayer on the lead frame main body 111. The base coating 120 and the top coating 130 containing impurities are laminated in this order, and the region exists on the surface of the top coating 130, and the region bonded to the reflector 170 among the regions is a first region, When the region bonded to the sealing portion 180 is the second region, the atomic concentration of bismuth exceeds the atomic concentration of germanium in the first region, and the atomic concentration of germanium in the second region is the atomic concentration of bismuth. It is going up. [Selection] Figure 1 |