With the continuous advancement of infrared detector technologies, the demand for the third generation of infrared detector technologies is becoming obvious gradually. Because of the factors of interband transition principle, dark current restrain effect and mature material fabrication technique etc., InAs/GaSb superlattice material becomes the primary choice for the fabrication of the third generation of infrared detectors. The main methods for the fabrication of InAs/GaSb mesa-focal plane arrays are wet etching, dry etching and the combination of dry and wet etching. These three kinds of etching methods have their advantages and disadvantages. The wet etching is suitable for the fabrication of single pixel or the focal plane array with less pixels. Among the wet chemical etching, the solution with phosphoric acid performs best. The dry etching is suitable for the fabrication of large arrays with small pixel spacing. The dry etching using Cl+ and the combination of Cl+ /CH3+ exhibit good etching results. The combination of dry and wet etching is used to add wet chemical etching after dry etching in order to eliminate etching damage and hence enhance device performance. The three kinds of etching methods are presented and analyzed.