This work investigates the reactive ions etching (RIE) physical properties of n-type ZnO using H2/CH4 and H2/CH 4/Ar mixtures by varying the gas flow ratio, the radio-frequency (rf) plasma power and the chamber pressure. Atomic force microscopy (AFM) results and surface topographies are discussed. Although the etching rate of the n-ZnO at an H2/CH4 flow rate of 100/0 sccm, a work pressure of 100 mTorr and an rf power of 300 W is lower than under any other conditions, the rms roughness of 43.78 nm is the highest, and supports the application of roughened transparent contact layer (TCL) in light-emitting diodes (LEDs). The dynamics associated with the high etching rate were highly efficient at an H2/CH4/Ar flow rate of 38/5/57 sccm, a work pressure of 150 mTorr and an rf power of 300 W. In addition, the ZnO with thermal annealing were studied. The slower etching rate of annealed n-ZnO is observed due to an increase the crystal quality of the ZnO films after thermal annealing which consists with the x-ray diffraction (XRD) results.
|Journal||Proceedings of SPIE - The International Society for Optical Engineering|
|State||Published - 1 Dec 2008|
|Event||Optoelectronic Materials and Devices III - Hangzhou, China|
Duration: 27 Oct 2008 → 30 Oct 2008
- Dry etching
- Reactive ions etching