Photocurrents in a metal-semiconductor-metal photodetector

Investigation of the dark electrical characteristics of the lateral metal–semiconductor–metal photodetectors using two‐dimensional numerical simulation

“…One‐dimensional calculations, based on the drift‐diffusion model 9–11, were used to study the transient and the steady state characteristics of the MSM‐PD under dark and illuminated conditions. However, because of the planar nature of the MSM structure, the electric field and current densities are two‐dimensional, and therefore 1D models remain unsatisfactory in studying the characteristics of the MSM‐PD.…”

High-speed nanoscale metal-semiconductor-metal photodetectors with terahertz bandwidth

“…A pulsed laser with pulse width much less than the response time of the photodetector (<0.5 ps) illuminates the device. The photo-generated current I MSM (t) can be found by solving the continuity equation as in (Sarto and Zeghbroeck 1997). The solution is found by approximating the device in 1-D, which holds as long as the penetration depth δ of the incoming light is much less than the finger spacing L. The solution is the infinite series:…”

Design of Thin-Film Lateral SOI PIN Photodiodes with up to Tens of GHz Bandwidth

“…2, this f tr reduction is observed on the Atlas simulation curve for L i greater than 2μm, when compared to the fast drift modeled curve that assumes full depletion of the I-region. In order to estimate the time t di f f for the diffusion of electrons through a P region of thickness L = L i − L zd , we can use the equation derived for a time-dependent sinusoidal electron density due to photogeneration in the P layer from the electron diffusion equation (Sarto& Zeghbroeck, 1997;Zimmermann, 2000) and, from there, derive the related -3dB frequency, Comparison of the PIN diode transition frequency given by Atlas simulations, by our model assuming drift only (full depletion hypothesis)(eq. 39), and by our model assuming both drift and diffusion mechanism (eq.…”