Wet etching can effectively remove the damage caused by mechanical effects during the back thinning process of chips, and improve the quantum efficiency of devices. In order to obtain a suitable wet etching method, three different acidic indium antimonide etching solutions were studied, mainly consisting of hydrofluoric acid, hydrochloric acid and lactic acid. The optimal etching solution system was selected based on the characterization results of metallographic microscopy and atomic force microscopy. On this basis, the concentration and ratio of hydrofluoric acid etching solution were further optimized, and the etching rate and consistency of the etching solution were studied. Finally, the optimized etching solution was used to treat the indium antimonide chip, and the performance of the chip at 77 K temperature was studied. The planar results show that the etching solution can effectively remove the damage on the chip surface, and the device voltage signal reaches 485 mV. The successful application of wet etching technology in surface treatment of chip back thinning has important significance for the research of indium antimonide back treatment technology.