Nonpolar a-plane light-emitting diode with an in-situ SiNx interlayer on r-plane sapphire grown by metal-organic chemical vapour deposition

We report on the growth and fabrication of nonpolar a-plane light emitting diodes with an in-situ SiN x interlayer grown between the undoped a-plane GaN buffer and Si-doped GaN layer.X-ray diffraction shows that the crystalline quality of the GaN buffer layer is greatly improved with the introduction of the SiN x interlayer.The electrical properties are also improved.For example,electron mobility and sheet resistance are reduced from high resistance to 31.6 cm 2 /(V · s) and 460 /respectively.Owing to the significant effect of the SiN x interlayer,a-plane LEDs are realized.Electroluminescence of a nonpolar a-plane light-emitting diode with a wavelength of 488nm is demonstrated.The emission peak remains constant when the injection current increases to over 20 mA.