以三氯硅烷(TCS)和氨气分别作为低压化学气相沉积(LPCVD)氮化硅薄膜(SiNx)的硅源和氮源,以高纯氮气为载气,在热壁型管式反应炉中,借助椭圆偏振仪和原子力显微镜,系统考察了工作总压力、反应温度、气体原料组成等工艺因素对SiNx薄膜沉积速率和表面形貌的影响.结果表明:随着工作压力的增大,SiNx薄膜的沉积速率逐渐增加,并产生一个峰值.随着原料气中NH3/TCS流量比值的增大,SiNx薄膜的沉积速率逐渐增加,随后逐步稳定.随着反应温度的升高,沉积速率逐渐增加,在830℃附近达到最大,随着反应温度的进一步升高,由于反应物的热分解反应迅速加剧,使得SiNx薄膜的沉积速率急剧降低.在730-830℃的温度范围内,沉积SiNx薄膜的反应表观活化能约为171kJ/mol.在适当的工艺条件下,制备的SiNx薄膜均匀、平整.较低的薄膜沉积速率有助于提高薄膜的均匀性,降低薄膜的表面粗糙度.
Silicon nitride thin films (SiNx) were prepared on silicon wafers from SiHCl3 (TCS)-NH3-N2
system via low pressure chemical vapor deposition (LPCVD) from 730℃ to 830℃ in a hot-wall horizontal tubular reactor.
By spectroscopic ellipsometer and Atomic Force Microscope (AFM), the growth rate and surface morphology of the films were investigated with various
deposition parameters, including total pressure, substrate temperature and reactive gas feed ratio. As total pressure increases, growth rate increases
at lower pressure and then decreases at higher pressure. The dependence of growth rate on substrate temperature is similar to that of total pressure.
However, as NH3/TCS ratio increases, growth rate gradually increases and eventually amounts to a constant. The apparent activation energy of the
reaction from 730℃ to 830℃ is about 171kJ/mol. AFM results reveal that lower growth rate is favor to improve film uniformity. SiNx
films with promising surface roughness can be prepared under appropriate deposition conditions.
参考文献
| [1] | Gwilliam R M, Shannon J M, Chen S M, et al., Surf. Coat. Tech., 1997, 93: 269--273. [2] Stamper A K, Pennington S L. J. Electrochem. Soc., 1993, 140: 1748--1752. [3] Kobayashi I, Ogawa T, Hotta S. Jpn. J. Appl. Phys., 1992, 31: 336--342. [4] 王晓泉, 杨德仁, 席珍强. 材料导报, 2002, 16: 23--25. [5] Sarita T, Satake T, Adachi H, et al., J. Electrochem. Soc., 1994, 141: 3505--3511. [6] Zambom L S, Mansano R D, Furlan R, et al., Thin Solid Films, 1999, 343--344: 299--301. [7] Han S S, Jun B H, No K. J. Electrochem. Soc., 1998, 145: 652--658. [8] Sinha A K, Levinstein H J, Smith T E, et al. J. Electrochem. Soc., 1978, 125 (4): 601--608. [9] Motojima S, Iwamori N, Hattori T. J. Mater. Sci., 1986, 21: 3836--3842. [10] Nikolski B P (eds.). Physical Chemistry, Chemistry Press, Leningrad, 1987. 772. [11] Peev G, Zambov L, Yanakiev Y. Thin Solid Films, 1990, 189: 275--282. |
- 下载量()
- 访问量()
- 您的评分：
-
10%
-
20%
-
30%
-
40%
-
50%