| 摘要 |
A method of preparing nanocolumns of zinc oxide (ZnO) on silicon substrates by radio frequency (RF) magnetron sputtering is disclosed. The process is performed using ZnO5 targets of 99.999% purity, in the presence of argon and oxygen gases, RF power of 100 to 300 Watt, at substrate temperature of 300 to 600°C and sputtering pressure of 1 to 10 mTorr. The optimum oxygen percentage over total mixture of argon and oxygen found to deposit ZnO layers of uniform thickness, with dense and fine nanocolumns, is 5 to 10% O2. The nanostructured TCO synthesized can be deposited on top of an LED structure to impose10 rough surface properties, which are useful in improving LEE and reducing light loss. In addition, the average optical transmittance of the ZnO film is 78% in the visible range of 470 nm. The present invention demonstrates advantages such as catalyst-free sputter deposition, formation of dense and uniform ZnO nanocolumn arrays, improved LEE and high transmission in visible spectral range, leading to suitable application in blue InGaN-based15 LEDs. |
