| 摘要 |
PURPOSE:To facilitate the assembly for high reliability, by forming inversion type isolated regions by selective diffusion from windows of insulating films provided on both surfaces of a substrate and then forming each region for cutting in mesa type control rectifying elements. CONSTITUTION:Lattice windows facing to each other are provided on SiO2 films provided on upper and lower surfaces of an N type Si substrate 1 to selectively diffuse P type impurity therefrom being joined at the center to form a P type isolated region 11. After the removal of the SiO2 film on the both surfaces, P type diffused layers 2, 3 are formed further to form an N type emitter layer 4. Next, a mesa etched groove 6 reaching the first base layer 1 deeper than junction J2 is formed, which is cut at the point of the P type isolated region 11 into individual pellets for a mesa type control rectifying element. This method allows easy assembly and stable insulating films of the junction to enhance reliability. |
