Wet Chemical Etching of Antimonide-Based Infrared Materials

【摘要】 The roughness and the crystallographic orientation selectivity of etched antimonide-based infrared materials are examined and are used to optimize the chemical mesa etching process of the InAs/GaSb superlattice photodiode with the goal of reducing the dark current.The etchant used is based on phosphoric acid（H₃PO₄）,citric acid（C₆H₈O₇） and hydrogen peroxide（H₂O₂）.The roughness of the mesa sidewalls and etching rates are compared and used to find an optimized etchant,with which we obtain optimized mid-wavelength infrared photodiodes possessing an R_OA value of 466Ω·cm² and a detectivity of 1.43 × 10¹¹ cm·Hz^1/2W^-1.Crystallographic orientation selectivity is seen in InAs etching,and also is seen in the InAs/GaSb superlattice wet chemical etching process.更多还原

【Abstract】 The roughness and the crystallographic orientation selectivity of etched antimonide-based infrared materials are examined and are used to optimize the chemical mesa etching process of the InAs/GaSb superlattice photodiode with the goal of reducing the dark current.The etchant used is based on phosphoric acid（H₃PO₄）,citric acid（C₆H₈O₇） and hydrogen peroxide（H₂O₂）.The roughness of the mesa sidewalls and etching rates are compared and used to find an optimized etchant,with which we obtain optimized mid-wavelength infrared photodiodes possessing an R_OA value of 466Ω·cm² and a detectivity of 1.43 × 10¹¹ cm·Hz^1/2W^-1.Crystallographic orientation selectivity is seen in InAs etching,and also is seen in the InAs/GaSb superlattice wet chemical etching process.更多还原