High-uniformity 2 × 64 silicon avalanche photodiode arrays with silicon multiple epitaxy technology

In this paper, high-uniformity 2×64 silicon avalanche photodiode (APD) arrays are reported. Silicon multiple epitaxy technology was used, and the high performance APD arrays based on double-layer epiwafers are achieved for the first time, to the best of our knowledge. A high-uniformity breakdown voltage with a fluctuation of smaller than 3.5 V is obtained for the fabricated APD arrays. The dark currents are below 90 pA for all 128 pixels at unity gain voltage. The pixels in the APD arrays show a gain factor of larger than 300 and a peak responsivity of 0.53 A/W@M = 1 at 850 nm (corresponding to maximum external quantum efficiency of 81%) at room temperature. Quick optical pulse response time was measured, and a corresponding cutoff frequency up to 100 MHz was obtained.