具有小面积雪崩区域和大面积吸收区域的SACM结构4H-SiC紫外雪崩光电探测器的研究

项目名称： 具有小面积雪崩区域和大面积吸收区域的SACM结构4H-SiC紫外雪崩光电探测器的研究

项目编号： No.61307047

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 无线电电子学、电信技术

项目作者： 洪荣墩

作者单位： 厦门大学

项目金额： 28万元

中文摘要： 本项目综合考虑影响SiC探测器性能的诸多因素，通过芯片结构的理论设计和制备工艺的优化，着重研究抑制探测器暗电流和提高探测率的方法。主要开展具有小面积雪崩区域和大面积吸收区域的雪崩-吸收-电场调节-分离结构4H-SiC紫外雪崩光电探测器（APD）的研究。由于SiC本身材料缺陷的局限性，导致了SiC APD容易提前击穿，成品率下降。小面积器件可以降低缺陷的影响。然而为了充分吸收光信号，又需要尽可能地增大器件面积。本项目提出的具有小面积雪崩区域和大面积吸收区域的4H-SiC APD可在不影响器件对光信号的吸收前提下，极大幅度地减小材料缺陷对器件的影响。此外，电场调节层的引入可大幅度降低器件的工作电压。同时进行P型4H-SiC的欧姆接触与氧化硅/氧化铝复合钝化/抗反射层的研究，以减小漏电流、提高光入射并实现器件的良好隔离。预期研制探测器将达到较高合格率，具有较低漏电流、较高光响应度和探测率。

中文关键词： 4H-SiC；紫外；光电探测器；雪崩；

英文摘要： In this work, according to the factors affecting the performance of SiC detector, we are going to design a novel photodiode structure and optimize the fabrication technology to suppress the dark current and improve the detectivity. we will study the performance of separated-avalanche-charge -multiplicaiton (SACM) 4H-SiC UV avalanche photodiode (APD) with small avalanche area and large absorption area. To reduce the premature breakdown effect of defect on the device, small area APD could be used. However, to make sure the enough absorption of the photons, the large area APD should be applied. Therefor, the novel SACM stucture of the 4H-SiC UV avalanche photodiode with samll avalanche area and large absorption area will decrease significantly the possibility of the premature breakdown of the 4H-SiC APD without weakening the absorption of the photons. And the exist of the charge layer could lower substantially the function voltage of the APD. Meanwhile, for reducing dark current, improving the incidence light and providing stable passivation, the P-type 4H-SiC ohmic contact and the SiOX/Al2O3 dual layers as an passivation/anti-reflection layer will be studied as well. The expected 4H-SiC APD will have low dark current, high photoresposivity, detectivity and high UV/visible rejection ratio. And the qualified rate o

英文关键词： 4H-SiC；ultraviolet；photodiode；avalanche；