| 摘要 |
PURPOSE:To improve the manufacturing yield by decreasing crystal defects by a method wherein an Si3N4 film with a thickness of 1,000-1,500Angstrom and refractive index of 1.80-1.85 is used as the protection film in forming an inpurity diffused layer in a semiconductor substrate by using a diffusion protection film. CONSTITUTION:An N type GaAsP layer 1b is grown on an N type GaAs layer 1a, and the Si3N4 film 2 with a thickness of 1,000-1,500Angstrom and a refractive index of 1.80-1.85 is grown thereon by the CVD method. This is coated with a photo resist film 3 and window holes 4 for selective diffusion are bored therein. Next, the film 2 exposed in the holes 4 is removed by dry etching with CF4 gas or the like, resulting in the generation window holes 5 for diffusion therein. Diffused layers 6 are formed by diffusing a P type impurity only into the holes 5 after removal of the film 3. Thereafter, the whole surface is covered with an insulation film 7, and grooves 8 are bored by corresponding to the diffused layers 6. A P-side electrode 9 in contact with the diffused layers 6 is adhered by extension on the film 7, and an N-side electrode 10 is adhered on the back of the layer 1a. Thus, the element is increased in density by making accurate the control of the diffused layers 6. |
