| 摘要 |
PURPOSE:To obtain a high-frequency high-output Si bipolar transistor by a method wherein a beryllia insulating substrate is bonded previously to a transistor chip, and a matter formed by integrating the beryllia piece and the transistor chip in one body is sticked to be put in a package. CONSTITUTION:Both the surfaces of a beryllia substrate 15 are metalized 16 according to molybdenum, for example, and the substrate having the surface thereof finished with gold plating is prepared. Then, the back side of a semiconductor wafer 13 is sticked to be bonded to the prepared beryllia substrate 15. Bonding thereof is performed by using a comparatively low melting point solder material 14 such as solder, an Au-Sn alloy, an Au-Ge alloy or an Au-Si alloy, etc., by heating from both the sides of the semiconductor wafer and the beryllia substrate pressing uniformly, and the solder material put between both is molten to attain bonding. By cutting thus obtained two layer structure of the semiconductor wafer 13 and the beryllia substrate 15 in a lattice type using a dicing saw, transistor chips having the beryllia substrates on the backs can be manufactured. The transistor chip 21 having the beryllia substrate constructed in such a way is sticked to be put in a package using a solder material of melting point lower than the solder material used before or bonding paste. |
