We report on the formation of Ohmic contacts with low resistance and high thermal stability to N-face n-GaN for vertical structure light emitters using a Ti(50nm)/Pt(50nm)/Au(50nm)metal scheme,where the Pt layer is in...We report on the formation of Ohmic contacts with low resistance and high thermal stability to N-face n-GaN for vertical structure light emitters using a Ti(50nm)/Pt(50nm)/Au(50nm)metal scheme,where the Pt layer is introduced as a blocking layer to suppress the diffusion of Au onto the N-face n-GaN surface.It is shown that unlike the conventional Ti/A1/Ti/Au contacts,the Ti/Pt/Au contacts exhibit an Ohmic behavior with a relatively low specific contact resistivity of 1.1×10^(-4)Ω.cm^(2) even after annealing at 350℃.X-ray diffraction(XRD)measurements by synchrotron radiation and Auger electron spectroscopy(AES)examination are performed to understand the effects of heat treatment.展开更多
基金Supported by the National Natural Science Foundation of China under Grant Nos 60506001,60976045,60836003,60776047 and 61076119the National Basic Research Program(2007CB936700)the National Science Foundation for Distinguished Young Scholar under Grant No 60925017.
文摘We report on the formation of Ohmic contacts with low resistance and high thermal stability to N-face n-GaN for vertical structure light emitters using a Ti(50nm)/Pt(50nm)/Au(50nm)metal scheme,where the Pt layer is introduced as a blocking layer to suppress the diffusion of Au onto the N-face n-GaN surface.It is shown that unlike the conventional Ti/A1/Ti/Au contacts,the Ti/Pt/Au contacts exhibit an Ohmic behavior with a relatively low specific contact resistivity of 1.1×10^(-4)Ω.cm^(2) even after annealing at 350℃.X-ray diffraction(XRD)measurements by synchrotron radiation and Auger electron spectroscopy(AES)examination are performed to understand the effects of heat treatment.