| Popis: |
The interface-alloy technique has been used to produce heterojunctions between GaAs and InSb. X-ray and Kossel line patterns show that, despite the relatively large 14% lattice mismatch between the semiconductors, these heterojunctions are single-crystal. Photocurrent and current-voltage measurements are explained by a model for the heterojunction band structure in which the salient feature is a region of the order of 60 A long which has a linearly-graded energy gap joining the GaAs to the InSb. The photocurrent occurs via hot carriers generated in the graded-gap region which traverse this region (with a mean free path of approximately 20 A) to the heterojunction barrier maximum. The results of the capacitance-voltage measurements are consistent with the current-voltage and photocurrent measurements evaluated in terms of the graded-gap heterojunction model. |
