摘要
在硅基光子学中,由于锗材料在通信波段有响应并且可以与CMOS工艺兼容,高性能锗基光电探测器成为近年来的研究热点。然而,对于超薄锗薄膜来说,低量子效率和高表面复合,尤其是在近红外波段,限制了其发展和应用。如今,实际的应用要求更小尺寸,更低功耗,高响应度以及快响应速度的光电探测器。在本文中,我们首先提出并制作了锗-石墨烯光电探测器,该探测器由一层20 nm的锗薄膜和单层石墨烯组成。探测器利用石墨烯透明且全谱吸收的特性以及锗材料在红外可以实现从紫外到近红外的宽谱探测;光电导增益可以达到155,响应度可以达到66.2 A W~(-1),该结果是相同结构纯锗基探测器性能的4倍,是纯石墨烯探测器性能的1000倍。这种性能的增强来源于光生载流子在材料界面的有效分离和转移。该结果为今后实现小尺寸、高性能硅基光芯片提供了一个范例,同时,该探测器也在成像、传感和其他光电子领域有着广泛的应用。
引文
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