High-performance metal-semiconductor-metal deep-ultraviolet photodetectors based on homoepitaxial diamond thin film

The authors report on the high-performance metal-semiconductor-metal planar photoconductors based on unintentionally doped homoepitaxial diamond thin films. The photoconductors exhibit a discrimination ratio up to 108 between 210nm and visible light. The spectral responsivity at 220nm is about 6A∕W biased at 3V, corresponding to a photoconductivity gain of 33. Time-resolved photoresponse measurements using a pulsed 193nm laser show that the response time is smaller than the pulse width of 10ns.