本論文主旨為將矽酸鉿材料作為MIS 結構氧化層並研究其光電流響應。矽酸鉿氧化層在高溫熱處理後會產生相分離現象，形成二氧化鉿奈米微晶分佈在氧化層裡。研究中利用共同濺鍍的方式沉積矽酸鉿氧化層，製成金氧半(Al/Hf Silicate/Si)結構，並調變不同的氧化層厚度及退火溫度來探討矽酸鉿的結晶、相分離特性以及其光響應特性。
實驗中探討不同的氧化層厚度及退火溫度對元件光響應的影響，900 ℃以下的退火，光響應電流及暗電流皆會隨著厚度增加而減少；而經1100 ℃退火後，厚度越厚可觀察到越大的光響應電流以及較低的暗電流，因此有高的亮暗電流比，此外觀察到明顯的電流遲滯現象。從TEM 圖中觀察，發現相分離的現象會受到半導體表面應力的影響，遠離半導體表面之氧化層有越明顯的相分離及結晶區域，致使越厚的氧化層表面形成高密度的奈米結晶結構，可能因此成為電流遲滯與高光響應電流的主因。

In this paper, the objective of the hafnium silicate material as a MIS structure of oxide layer and to study their photoresponse. Hafnium silicate oxide layer after heat treatment at high temperature will produce the phenomenon of phase separation, the formation of hafnium dioxide in the nano-crystals oxide layer. Research on the use of co-sputter deposition of hafnium silicate oxide layer, made of semi-metal-oxide (Al / Hf Silicate / Si) structure, and modulation of different oxide thickness and annealing temperature to explore the crystallization of hafnium silicate, phase separation characteristics as well as their optical response characteristics.
Experiments to explore different oxide thickness and annealing temperature of components in response to the effects of light, 900 ℃ annealing below, photo current and dark current will decrease with the increase in thickness; and by 1100 ℃ annealing, the thickness can be thicker observed that the greater the photoresponse and lower dark current, it is a high dark to current ratio, and the obvious observation of hysteresis current. From the TEM morphology, found that the phenomenon of phase separation would be the impact of semiconductor surface stress, away from the interface between semiconductor and oxide layer of the more obvious phase separation and crystallization of the region, resulting in a thicker oxide layer formed on the surface of the high-density nano-crystalline structure, may become sluggish and the current response to high light the main current.

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