The effect of hole versus electron photocurrent on microwave—Optical interactions in IMPATT oscillators

The effect of hole versus electron photocurrent on the microwave properties of IMPATT oscillators is presented and correlated with static
I-V
characteristics. The composition of the photocurrent was altered by fabricating both flip-chip (FC) and top-mounted (TM) devices and using an optical source with an absorption depth comparable to both the depletion-layer thickness and substrate diffusion length. The importance of the order of magnitude difference in effect of hole versus electron photocurrent is discussed.