CURRENT-VOLTAGE CHARACTERISTICS OF P-P ISOTYPE INGAALP GAAS HETEROJUNCTION WITH A LARGE VALENCE-BAND DISCONTINUITY

Current-voltage characteristics of p-InGaAlP/p-GaAs heterojunctions ha ve been investigated. A heterospike at the heterointerface of InGaAlP/ GaAs generated a large voltage drop, which strongly depended on the Al composition and the acceptor concentration of InGaAlP layer. Insertio n of an intermediate layer of InGaP, which had an intermediate band ga p between those of InGaAlP and GaAs, significantly reduced the voltage drop by an order of 10(3). These experimental results were in good ag reement with the theoretical calculation accounting for a large valenc e band discontinuity between InGaAlP and GaAs.