METHOD FOR ANISOTROPY DRY ETCHING OF GAN

摘要

PURPOSE: A method for anisotropy dry etching of GaN is provided to gain a high potentiometric selectivity coefficient between AlGaN and GaN. CONSTITUTION: An AlGaN layer and a GaN layer is laminated on a substrate to make a nitride semiconductor. The nitride semiconductor is loaded into an ICP(Inductively Coupled Plasma), ECR(Electron Cyclotron Resonance), or MRIE(Magnetically enhanced Reactive Ion Etch) machine. Inside the machine, the pressure is controlled as 10 mTorr, and the temperature is fixed on 20C. The GaN layer is etched by changing the plasma output power(0¯3000W), RF(Radio Frequency) table output power(0¯500W), and the amount of injecting oxygen (0¯8SCCM(Standard Cubic Centimeter per Minute)). After finishing the etching process, the nitride semiconductor is washed using a mixed solution to remove the oxygen. the mixed solution is composed of deionized water, ammonium fluoride and HF.