Surface Nitrogen Passivation And Physical Characteristics Of GaSb Material

GaSb material is an important semiconductor in ?-? compound semiconductor material,which is the first choice to realize high performance laser in middle-infrared range and has many applications in military and civilian fields,such as laser guidance,optical communication and so on.However,the surface chemical properties of GaSb material is extremely active,which has high interface state density.It effects on the performance of the device seriously.The surface passivation can effectively reduce the surface state density and improve the surface luminescence intensity.Therefore,it's significant to carry out the research work of surface passivation of GaSb materials.Aiming at the disadvantages of wet sulfur passivation such as the new surface states problem and passivation process is not easy to control.This paper put forward a method of nitrogen passivation which is based on atomic layer etching.We use precisely atomic layer etching technology of GaSb material surface by nitrogen plasma in the plasma enhanced atomic layer deposition(PEALD)system to acquire the best conditions of nitrogen passivation.The surface oxide layers were reduced and the photoluminescence intensity of n-type GaSb material was improved through the treatment of different nitrogen passivation experiments.The change of experimental conditions in nitrogen passivation will have an important influence on the energy levels of Ga(3d)and Sb(3d)and the corresponding chemical bonds.Nitrogen passivation has better stability according to the passivation stability test within 15 days,which can inhibit the secondary oxidation problem.Moreover,the samples also have a good flatness after passivation treatment according to the AFM experiment.In this paper,the treatment method of GaSb material by nitrogen passivation shows favourable passivation effect and also has a better stability.Therefore,this research work lays the foundation for enhancing performance of GaSb based semiconductor laser and improving passivation process of GaSb based semiconductor laser.