Fig. 1. InGaAs detector type diagram：(a) plane type InGaAs detector；(b) mesa type InGaAs detector

Fig. 2. Micro-mesa type InGaAs detector

Fig. 3. Schematic diagram of device fabrication process

Fig. 4. The relationship between SiN_x and InP etching depth with etching time

Fig. 5. Physical diagram of part of devices：(a) image of device morphology taken by a confocal microscope; (b) InGaAs morphology of a 2 μm isolated trench micromesa device; (c) micromesa crosstalk test structure physical diagram

Fig. 6. Crosstalk test structure diagram.

Fig. 7. Comparison of crosstalk test results of micromesa devices and planar devices when isolation trenches etching does not enter the absorption layer

Fig. 8. Comparison of crosstalk test results of micromesa devices and planar devices when isolation trenches etched into the absorption layer.

Fig. 9. Blackbody response signal test structure diagram

Fig. 10. Dark current of 5 μm pixel pitch plane and micromesa structure.

Fig. 11. Dark currents of planar devices and micromesa devices with different isolation groove widths when the isolation trench etching does not enter the absorption layer.

Fig. 12. The dark current of planar devices and micromesa devices with different isolation groove widths when the isolation trench etches into the absorption layer

Fig. 13. The activation energy obtained when the isolation trenches etching does not enter the absorption layer

Fig. 14. The activation energy obtained when the isolation trenches etching enters the absorption layer