超薄多晶硅薄膜具有优异的压敏特性。铝诱导层交换(ALILE)制备多晶硅薄膜具有成膜温度低薄膜性能优良等特点。利用ALILE方法在玻璃基底上低温条件下制备了50 nm超薄多晶硅(poly-Si)薄膜, 并对薄膜微观结构及压阻特性进行了研究。Raman光谱在521 cm-1出现尖锐、对称的特征峰, 表明超薄多晶硅薄膜晶化状态良好。此外, 在拉曼光谱480 cm-1处没有明显出现a-Si的Raman特征峰也说明制备的poly-Si薄膜样品完全结晶;XRD光谱表明ALILE制备薄膜在(111)和(220)晶向择优生长, 晶粒尺寸约5 μm;霍尔效应测试结果表明: ALILE制备薄膜为p型掺杂, 空穴浓度为9×1018～6×1019 cm-3;压阻特性研究表明: ALILE超薄多晶硅薄膜应变系数(GF)达到了60以上, 且与薄膜厚度相关;应变温度相关系数(TCGF)在-0.17～0%℃范围内;电阻温度相关系数(TCR)在-0.2～-0.1%℃范围内。ALILE超薄多晶硅薄膜具有GF大、TCGF小和TCR小等特点。因此, 有望在压力传感器领域得到应用。

Poly-Si film, due to its favorable piezoresistive properties, has been widely used in piezoresistive sensors. The previous researches have shown that the ultra-thin poly-Si film have better piezoresistive properties than common poly-silicon film, and have promising future of application. A promising method to obtain large grained high quality poly-silicon films by low-temperature crystallization of an amorphous precursor material is the aluminum-induced layer exchange (ALILE). In this paper, ultra-thin poly-Si films were prepared by aluminum induced layer exchange (ALILE). Experimental results of Raman spectroscopy show that a narrow and symmetrical Raman peak at the wave number of about 518 cm-1 was observed for all samples, indicating that the films were fully crystallized. XRD results show that the crystallites of ultra-thin poly-silicon layer were preferably (111) and (220) oriented. Hall affect measurements show that hole concentration of the films (p-type) were between 9×1018 and 6×1019 cm-3. Restorative properties show that the piezoresistors exhibit gauge factors (GFs) up to 60, with temperature coefficients of GF (TCGF) between -0.17～0%℃ and temperature coefficients of resistance (TCR) between -0.2 and -0.1%℃. The study of the ultra-thin poly-Si films by ALILE is completed, and the study results lay a foundation for application of the film to piezoresistive sensor.