| 摘要 |
PURPOSE:To restrict formation of impurity sequence improving electric characteristics by means of trapping aluminium heat diffusing to silicon epitaxial growth layer by a method wherein oxygen is ion-implanted to improve crystali- zation by means of solidus epitaxial growth resulting from later heat treatment. CONSTITUTION:After forming SOS film 2 with silicon layer on sapphire substrate 1, oxygen is ion-implanted in the arrowmark direction 13 around the interface of Si/sapphire leaving a crystalline layer around the surface of said SOS film to non-crystalize 14 the other SOS film and around the interface of Si/sapphire. Then the crystalline layer near the surface toward Si/sapphire interface is solidus epitaxially grown by means of heat treatment. Through these procedures, the thermal diffusion of aluminium from said sapphire substrate 1 to said SOS film may be prevented by said heat treatment restricting the formation of impurity order due to aluminium contained in said SOS film since the crystalization is improved and the oxygen ion-implated into Si/sapphire interface traps said aluminium. |
