STRUCTURE OF SUBMOUNT FOR PHOTO SEMICONDUCTOR ELEMENT

PURPOSE:To simplify the mounting process of an element in a submount as well as to realize the submount suitable for automatization by a method wherein the submount, which is used for mounting a chip of the light semiconductor element, is made of an electrical insulating material of pyrogenetic conductivity, more than one metalized patterns are provided on the surface thereof and a soldering pattern layer is further partially formed. CONSTITUTION:An Ni layer 56 is vacuum-evaporated on the back surface of a pyroconductive SiC ceramic substrate 51 to be used for a submount while the substrate 51 is being heated at temperatures of 400-500 deg.C and then the temperatures are lowered to about 200 deg.C for making an Au layer 57 coat, and a back-surface metalized layer is formed of these layers. Then, the substrate 51 is heated at 200-300 deg.C and a wiring layer 52 consisting of a Ti layer 61, an Mo layer 62 and an Au layer 63 is laminated for coating on the surface thereof. After that, the wiring layer 52 is made in the prescribed form and a laminated barrier layer 54 consisting of a Ti layer 64, an Mo layer 65 and an Au layer 66 is formed thereon. After then, a soldering pad 55 consisting of Pb and Sn is provided thereon and the substrate 51 is cut in the desired size. At this cutting time, the barrier layer 54 is a layer to be used for preventing an alloying reaction between the solder 55 and the Au layer 63.