活性離子蝕刻對氧化銦錫/矽異質接面二極體的影響及退火條件對氧化銦錫光電性質的影響

Abstract

探討矽晶片的表面處理對氧化銦錫/矽異值接面二極体的電性影響以及氧 化銦錫在不同氣氛下的退火處理後的光電性質的研究。矽晶片經過活性離 子蝕刻後，氧化銦錫/矽異值接面二極体的電性對P-型矽而言，將由歐姆 接面轉變成整流接面，且能障高度與理論常數隨著活性離子蝕刻的射頻功 率增加而變大。此現象歸因於經活性離子蝕刻的矽表面的淨正電荷的累積 與破壞。而蝕刻後的矽在經過退火處理後，氧化銦錫/矽異值接面二極體 有恢復成原始狀況的趨式。另外，將濺鍍於玻璃基板之氧化銦錫薄膜分別 在氧和氮的氣氛中退火處理，則見薄膜之可見光區透光率在退火處理之後 有顯著的提升。而在氮的氣氛中退火處理後，會造成氧化銦錫內氧空位和 霍耳移動率的增加，氧化銦錫薄膜的電阻率於退火處理後，降低約3.5倍 。 The effect of the silicon surface treatment on the current -voltage and capacitance-voltage characteristics of the ITO/Si heterojunction diodes and the electrical and optical charac- teristics of the annealed ITO films at the different atmosphere (an inert or oxidizing ambient) were investigated. When the Si substrate is etched by reactive ion etching prior to the depo- sition of ITO film, the current-voltage characteristics of ITO/ P-type Si heterojunction diodes transfer ohmic contact to rectifying contact and the barrier height and the ideality factor become larger with increasing the RIE RF power. The result is attributed to the net positive ion charge and defect on the damaged silicon surface. The characteristics of ITO/Si heterojunction has trended to recover the original characteris- tics after the etched silicon surface is annealed. In additional , the RF magnetron sputtered ITO films on glass substrate are annealed at nitrogen or oxygen atmosphere and the enchanted visible transmittance is observed. The oxygen vacancies and Hall mobility increase as ITO films are annealed at nitrogen atmos- phere and the electrical resistivity decreases 3.5 times.