壓應力對鎳片在非晶矽薄膜誘發側向結晶之影響

Abstract

本論文研究目的為使用一種低成本，可以替代昂貴鍍膜設備，產生金屬誘發非晶矽薄膜側向結晶之方法。使用鎳片施加265.8 MPa至2.857 MPa壓應力於非晶矽層上並熱處理後，進行AFM、SEM、EDS、Raman與XRD之分析。 當壓應力為268.8 MPa時做550℃一小時之熱處理，其表面鎳矽層厚度為185.95 nm，EDS分析其鎳含量為76.22 at%。壓應力2.857 MPa時，表面之鎳矽層為8.98 nm，EDS分析其鎳含量為0.33 at%。壓應力介於265.8 MPa與132.9 MPa時550℃一小時之熱處理，較難側向成長，壓應力介於38.2 MPa與3.7 MPa時在在熱處理的過程中已經開始側向成長。在移除壓應力與鎳片後用550℃熱處理側向成長速率皆約為3.3μm/h。壓應力2.857 MPa做550℃一小時之熱處理後移除鎳片再作550℃四小時之熱處理之試片以SIMS分析，其鎳殘留量約為30 counts。由拉曼光譜分析得知試片之結晶矽峰值位置在517.11 cm-1，為多晶矽之訊號。

The purpose of this study is to develop a low-cost fabrication method of metal induced lateral crystallization of amorphous silicon film, which can replace the expensive coating equipment. After executed compressive stress at the stresses ranging from 265.8MPa to 8.857Mpa and heat treated, the specimens were analyzed by AFM, SEM, EDX, Raman and XRD. After carried out compressive stress of 265.8MPa at 550℃ for 1h, the thickness of nickel silicide surface film was 185.95nm. EDS analysis indicated that the Ni content of the nickel silicide film was 76.22 at%. When the compressive stress executed with 2.857 MPa at 550℃ for 1 hr, the thickness of nickel silicide was 8.98 nm and EDS analyzed the Ni content was 0.33 at%. The nickel silicide was hard to form at the compressive stress between 265.8MPa and 132.9MPa at 550℃ for 1 hr. However the nickel silicide induced lateral crystallization was occurred at the compressive stress between 38.2MPa and 3.7MPa at 550℃ for 1 hr. After nickel sheet removed the compress stress and then annealed at 550℃, the lateral crystallization rate was 3.3 μm/h. The nickel concentration of the sample which was enforced with 2.857MPa at 550℃ for 1 hr and then nickel sheet removed and annealed at 550℃ for 4 hr was examined by SIMS. The residual nickel concentration was 30 counts. From Raman spectroscopy, the Raman signal at lateral crystallization region was 517.11 cm-1, the result showed that the grain was poly-grain by Raman signal.