Transient velocity assessment in gallium arsenide, and of other GaAs characteristics related to device functions

The final report for a 12-month program containing four tasks in two general areas of concern for GaAs device technology. Task 1 was to assemble and evaluate literature and other databases concerning high speed operation as assisted by velocity overshoot or ballistic transport; a bibliography of 232 items appears with this Report. Task 2 involved assessment of the probability of achieving ballistic or other maximized electron speed with various sub-micron geometry GaAs devices, and the report here emphasizes the higher probability of eventual success with vertically-oriented devices, especially HBTs. Task 3 involved literature and other database assessment for EL2 and other extrinsic properties of GaAs; it is noted here that, despite intense study by many, the atomic nature of EL2 is not determined, and that research on the high temperature defect chemistry of GaAs is desirable. Task 4 involved mapping measurements of EL2 and other properties of SI GaAs wafers, and the part of our work carried out in support of DARPA needs is described.