NORMAL-INCIDENCE EPITAXIAL SIGEC PHOTODETECTOR NEAR 1.3 MU-M WAVELENGTH GROWN ON SI SUBSTRATE

We report on the fabrication of photodetectors with a response near 1. 3 mu m wavelength using an epitaxial SiGeC alloy grown on a Si substra te. The active absorption layer of the SiCeC/Si pin photodiode consist s of a strained SiGeC alloy with a Ge content of 60% and a thickness o f 800 Angstrom. The device exhibits a peak response at 0.85 mu m with the response extending to 1.3 mu m and a cutoff wavelength at around 1 .55 mu m. The photocurrent response of the device versus reverse bias voltage saturates at 0.5 V. The leakage current density at the saturat ion voltage is 70 pA/mu m(2). These results may shed some light on Si- based SiGeC alloys for photodetector applications in the 1.3-1.55 mu m wavelength range. (C) 1996 American Institute of Physics.