摘要: | 本計畫目標為發展新式鈍化接觸技術(passivated contacts),要利用特殊的薄型”雙層鈍化”結構,可同時結合化學及物理(場效)的鈍化優勢,加上透明導電薄膜,使同時具有鈍化及導電性質,將可應用在矽基偵測器及太陽能電池上,使其具有高光電轉換效率及低暗電流的性質。 近年來提出了鈍化接觸”passivated contacts”技術,此方法藉由薄型氧化層解決鈍化問題,有低表面複合速率、載子選擇、低溫製程等優點,同時也可導電,因而被廣泛地研究著。美國的NREL團隊和喬治亞理工學院的Prof. Tao、德國的Fraunhofer ISE團隊、國立澳洲大學的Prof. Bullock和、荷蘭恩荷芬理工大學的Prof. Smit都在積極應用於太陽能電池上之研究。但這些研究主要在”單層鈍化”層上;但單一鈍化層的鈍化效果僅有化學或場效性質,以產生鈍化效應,而雙層鈍化層效應可進一步將化學及場效結合在一起,產生更好的鈍化效應。本計畫則要在本實驗室已發展的單層及最近發現厚型雙層薄膜鈍化層上,建立薄型雙層鈍化層之鈍化接觸技術,研究其物理機構, 技術及其應用。 目前本實驗室在薄型氧化層已建立不錯的成果,也應用在矽基鍺光偵測器上;我們在矽基光偵器上用單一層氧化矽層作鈍化,在工作波段為1550nm時取得暗電流10-6A與光響應0.36A/W等相關成果。在本計畫將使用雙層鈍化層結構,先製作鈍化特性與電性俱佳之薄型氧化層,然後再鍍一層相配的薄型鈍化層,研究它們的鈍化機制,包括介面fix charge density、次相組成與厚度等;最後應用於矽基光偵測器上,以進一步改善元件之暗電流及光電效率,使矽基鍺光偵測器有不輸三五族光偵測器之競爭力,對於發展發展矽基光電元件將有極大幫助。 ;The goal of this proposal is to investigate the new type of passivated contact, using special double passivated films with chemical and physical passivation effects, with transparent conductive film, and can be used on the Si-based photodetector and solar cell, improving its efficiency and dark current. Recently, passivated contact technology using thin oxide film to improve passivation with low surface recombination velocity, carrier choice, and low temperature process advantages, also with conduction of electricity attracted lots of attentions. However, these researches are on one layer of passivation film, and only possesses chemical or physical passivation effect. Double films can combine both of chemical and physical passivation effects, which can lead to more effective of passivation. In the proposal, we will develop this double layer passivation of the passivated contact technology. Our lab has experience on the thin oxide film, transparent conductive oxide, and Si/Ge photodetector. Recently, we have built the Si/Ge photodetector and have properties of dark current density of 0.146 mA/cm2 and photo-responsibility of 0.36 A/W in the wavelength of 1550 nm. In this proposal, we will use double layers of passivation films to develop new type of passivated contact. We will investigate its physical mechanism, and applied it on Si-based photodetector to improve its efficiency and dark current. |