提出一种基于SDB技术的非平面埋氧层SOI材料制备方法.其关键技术包括:通过干法刻蚀、高压氧化和淀积二氧化硅获得高质量非平面埋氧层;通过化学气相淀积多晶硅来形成键合缓冲层,并运用回刻光刻胶和化学机械抛光来实现键合面的局部和全局平坦化;通过室温真空贴合、中温预键合和高温加固键合来进行有源片和衬底片的牢固键合.基于该技术研制了有源层厚度为21μm、埋氧层厚度为0.943μm、顶面槽和底面槽槽高均为0.9μm的具有双面绝缘槽结构的非平面埋氧层新型SOI材料.测试结果表明该材料具有结合强度高、界面质量好、电学性能优良等优点.
A fabrication process of a novel SOI material with a non-planar buried oxide layer was developed using a series of key processes. A high quality non-planar buried oxide film was made by dry etching, thermal growth,and chemical-vapor deposition. A poly-silicon buffer layer for bonding was deposited by CVD and was planarized by photoresist block masking and chemical mechanical polishing. The active and substrate wafers were bonded by vacuum contacting at room temperature,with pre-bonding at a moderate temperature and final firming bonding at a high temperature. Based on these key processes,a novel SOI material with a non-planar buried oxide layer was fabricated. The structure includes an active layer with a thickness of 21μm,a buried oxide with a thickness of 0. 943μm, and self-aligned top and bottom trenches with thicknesses of about 0.9μm. The measurements indicate a high quality bonded interface with a large combining intensity and excellent electrical performance with a high breakdown electric field.