Rectification and intrinsic photocurrent of GaAs/Si photodiodes formed with pulsed-laser deposition at 1064 nm

摘要

With a rate of 1 nm per minute, thin-film p-GaAs has been deposited on n-Si with nanosecond laser pulses at 1064 nm. The samples revealed rectification with an uncommon power dependence on the forward bias. Furthermore, we noticed that the intrinsic photocurrent spectra sensitively depend on the deposition time. Increasing this duration from one to three hours shifts the maximum of the spectral device response from GaAs to Si. The result stresses the flexibility of pulsed-laser deposition to alter device properties in extremely simple ways.