Cm. Hurd et Wr. Mckinnon, 2-DIMENSIONAL NUMERICAL-SIMULATION OF THE PULSE RESPONSE OF A SEMIINSULATING INGAAS-FE PHOTODETECTOR, Journal of applied physics, 78(9), 1995, pp. 5756-5764
A calculation is described of the transient pulse response of a planar
metal-semiconductor-metal photodetector consisting of Schottky contac
ts made to an active layer of semi-insulating InGaAs:Fe that is suppor
ted on an InP:Fe substrate. The simulation uses a two-dimensional, dri
ft/diffusion calculation and includes external circuit elements. Reali
stic conditions are considered where the semi-insulating material is r
epresented by a two-level compensation model with Fe as a deep accepto
r and hole trap that compensates shallow n-type impurities. The calcul
ated results are compared directly with experimental ones for micron-s
cale devices described in the literature. The calculation gives a micr
oscopic picture of how trapping controls particularly the falling side
of the transient response, and it also shows how the measured perform
ance of the device can reflect the influence of typical external circu
it elements.