鋁摻雜氧化鋅奈米粒子光電特性之研究

Optical and Electrical Properties of Al-doped ZnO Nanoparticles

陳耀銘(Yao-Ming Chen) ； 林祐仲(Yow-Jon Lin)

《真空科技》 24卷4期 (2011/12) Pp. 17-23

https://doi.org/10.29808/JVSROC.201112.0003

摘要

本研究利用溶膠 - 凝膠法製作氧化鋅（ZnO）奈米粒子，探討摻雜不同濃度的鋁（Al）對ZnO 奈米粒子特性的影響；並利用ZnO奈米粒子製作光檢測器，探討元件光響應特性。經由掃描式電子顯微鏡、X光繞射分析、光致螢光光譜以及拉曼光譜量測得知奈米粒子的材料特性。實驗結果顯示，將Al摻入ZnO後，因Al與Zn離子半徑不同影響原子排列結構導致結晶性變差，進而增加多聲子散射致使非輻射復合機率增加。此外，觀測有無摻Al的ZnO所製作之光檢測器，結果顯示摻Al的元件電流值較未摻 Al的元件大，其原因為 Al3+ 取代 Zn2+會多出一個自由電子，使得載子濃度增加以及電阻率下降。然而，當Al摻雜濃度高於5%時，多聲子散射現象增加而使得電阻率再度上升。另外，關於元件光響應的反應速度探討得知，因摻雜Al的ZnO具有較多陷捕中心，因此摻Al的元件反應時間常數較未摻Al的元件大。

關鍵字

溶膠-凝膠法 ； 鋁摻雜 ； 多聲子散射 ； 光響應

並列摘要

This study investigates the effect of Al content on the optical, electrical and structural properties of the sol-gel Al-doped ZnO nanoparticles by x-ray diffraction, scanning electron microscopy, photoluminescence and Raman scattering measurements. When more Al are substituted into the ZnO system the difference in ionic radii of Zn2+ and Al3+ starts playing an increasingly important role causing the presence of the multiple phonons scattering stress in the Al-doped ZnO nanoparticles. It is shown that the multiple phonons scattering may lead to an increase in the probability of nonradiative recombination. The dark current and photocurrent of the Al-doped ZnO device are larger than those of the ZnO device, due to a combined effect of the increased substitutional-Al (AlZn) density and the increased carrier concentration. However above 5% Al doping, resistivity again increases with the increase in the multiple phonons scattering processes. The photoresponse studies show that the time constants of the Al-doped ZnO device are larger than those of the ZnO device. This is because of the higher trap density of the Al-doped ZnO device than the ZnO device.

並列關鍵字

Sol-gel ； Al-doped ； Multiple Phonons Scattering ； Photoresponse