Multicolor quantum well and superlattice infrared photodetector with grating structure optimization

We have designed an infrared photodetector which has a superlattice (SL), graded barriers and then multiple quantum wells (MQWs). The grating with fixed 2 μm period and different depth on detector was fabricated and its effects on detector's performance was discussed. The grating with 2 μm period and 1.3 μm depth shows the highest performance. The simulation of electromagnetic distribution in structure shows the same trend as experiment results.