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 substrate. The active absorption layer of the SiCeC/Si pin photodiode consists of a strained SiGeC alloy with a Ge content of 60% and a thickness of 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 saturation 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.