基于绝缘体上硅晶片的微机电系统红外光源

MEMS Infrared Emitter Based on SOI Wafer

提出了一种利用微机电系统（MEMS）制造工艺技术制备的硅基微型红外光源。该光源使用绝缘体上硅（SOI）晶片作为基底材料,其上沉积多晶硅材料并通过离子注入工艺实现材料的电阻加热发光特性,SOI晶片上的单晶硅层通过重掺杂实现辐射光背向吸收自加热效应。利用SOI晶片中的掩埋二氧化硅层为刻蚀停止层,通过背面深反应离子刻蚀（DRIE）技术制备微米量级的薄膜发光层结构。光源表面工作温度和辐射光谱分别通过红外热像仪和光谱辐射计测量得到。实验结果表明,该光源在表面温度约700 K时,1.3~14.5μm波长内的能量转换效率约为5.58%,光源的调制频率在50%的调制深度下接近40 Hz。

A micro-electro-mechanical systems（MEMS） infrared（IR） emitter is presented.The IR emitters are fabricated on silicon-on-insulator（SOI） wafer,and the resistance heating film on the SOI wafer used boron-doped polysilicon by ion implantation technology.The single crystal silicon on SOI wafer is designed as a heavily-doped infrared absorption layer for realizing the self-heating effect.The light-emitting layer is fabricated by using deep reactive ion etching（DRIE）process on the backside of SOI wafer,and the buried SiO2 layer of the SOI wafer is used as etching stop layer to control the thickness of light-emitting layer.The surface temperature and emission spectrum of IR emitter are measured by thermal imaging system and spectroradiometer.The experimental results show that in the case of surface temperature of about 700 K,the energy conversion efficiency is about 5.58% in the spectrum range of 1.3~14.5 μm.The experiments also show that the modulation frequency can reach to 40 Hz at 50% modulation depth.