InGaAsP/InP photodetectors targeting on 1.06 μm wavelength detection

• InGaAsP photodetectors targeting on 1.06 μm wavelength have been demonstrated.
• The dark current is dramatically lower than In0.53Ga0.47As detector.
• The detectivity at 1.06 μm is much higher comparing to In0.53Ga0.47As detector.
• The theoretical mechanisms are analyzed and compared to experimental results.

InP-based InGaAsP photodetectors targeting on 1.06 μm wavelength detection have been grown by gas source molecular beam epitaxy and demonstrated. For the detector with 200 μm mesa diameter, the dark current at 10 mV reverse bias and R0A are 8.89 pA (2.2 × 10−8 A/cm2) and 3.9 × 105 Ω cm2 at room temperature. The responsivity and detectivity of the InGaAsP detector are 0.30 A/W and 1.45 × 1012 cm Hz1/2 W−1 at 1.06 μm wavelength. Comparing to the reference In0.53Ga0.47As detector, the dark current of this InGaAsP detector is about 570 times lower and the detectivity is more than ten times higher, which agrees well with the theoretical estimation.