| 摘要 |
PURPOSE:To obtain an Si3N4 film of high quality without dissociation or evaporation of As by laminating the Si3N4 through an SiO on the surface of a semiconductor material having As as an ingredient element. CONSTITUTION:The Si3N4 is a stable insulating film and incorporates approximately double of a refractive index. Thus, the Si3N4 is effective for the reflection preventing film of a solar battery formed of a material having approx. 4 of refractive index such as GaAs or the like. However, it requires high temperature higher than 700 deg.C to form of silane and NH3. On the other hand, since a material having As as an ingredient element such as GaAs incorporates high vapor pressure of As, if the temperature exceeds 600 deg.C, the As is dissociated and evaporated to thus cause a defect on the surface. Therefore, the conventional reflection preventing SiO film is unstable, but when the Si3N4 is laminated thereon and the evaporation of the As is prevented by the SiO by means of a heat decomposition process with a temperature higher than 700 deg.C, thereby obtaining the Si3N4. Thus the surface can be stabilized and the reliability can be improved. |
