Published online by Cambridge University Press: 28 February 2011
A highly sensitive photodiode was fabricated with a metal-porous silicon junction. The spectral response was measured for the wavelength range from 400 nm to 1.075 μm. It was demonstrated that close to unity quantum efficiency could be obtained in the wavelength range of 630 to 900 nm without any anti-reflective coating. The detector response time is about 2 ns for a 9 volts reverse bias. The acceptance angle of photodiode is 2 times better than that of conventional Si detectors. The uniformity and stability were also studied. Possible mechanisms are discussed.