Research of high-performance uncooled infrared focal plane array detector with common-leg structure

Abstract

A novel micro bridge structure for uncooled vanadium oxide infrared focal plane array (IRFPA) detector was developed. This micro bridge used common-leg structure, which was shared by column adjacent pixels. Common-leg structure greatly increased the leg length, reducing the thermal conductivity, which could effectively improve the response rate and reduced the negative electron-transfer dissociation (NETD). Furthermore, the micro bridge adopted double-layer process to increase the area of the deck and the vanadium oxide, which could improve the filling rate and the detector performance. The detector array was 384×288 with 12 μm pixels. The readout integrated circuit (ROIC) adopted rolling-shutter mode for integration and a pixel-by-pixel mode for readout. The high reliability metal vacuum package was used for the device. The results showed that the NETD of the detector was less than 15 mK, and the response rate was greater than 44 mV/K. Its performance index could meet the requirements of civil and military applications.