SUBSTRATE CRYSTAL MATERIAL OF GROUP III-V COMPOUND SEMICONDUCTOR HAVING HALF INSULATING PROPERTY AND ITS PREPARATION

PURPOSE:To obtain easily the titled material having high specific resistance value in the whole length of substrate crystal material, by adding simultaneously two or more compensating impurities when a remaining carrier is compensated and group III-V compound semiconductor having half insulating properties is grown. CONSTITUTION:In a method wherein a remaining carrier is compensated and group III-V compound semiconductor having half insulating properties is grown, a compensating impurity to form one deep carrier trap level and at least one of other compensating impurities other than this compensating impurity are simultaneously added. This method can be applied to preparation of half-insulating substrate crystal material of InP by liquid capsule pulling method, other substrate crystal material of half-insulating compound semiconductor such as GaAs, Gap, etc. In Bridgman method, etc. besides the liquid capsule pulling method, one compensating impurity to form a deep carrier trap level and at least one of other compensating impurities are selected, and added simultaneously.