高温退火对PECVD硅化钛膜的影响

<正> 一、引言 以TiSi_2为代表的难熔金属硅化物,由于具有铝及掺杂多晶硅所不具备的特点,已成为VLSI中制作栅电极和互连线的重要材料。CVD法制备硅化钛膜的突出优点是台阶覆盖性好,有利于批量生产。然而,用卧式PECVD制备硅化钛膜的方法至今尚未见报道。 PECVD法淀积的硅化钛膜,必须经退火结构才能稳定。目前,常用瞬态退火和常规热退火(高温退火)两种方法。常规热退火能和常规工艺兼容,而瞬态退火则可减少原子的互扩散。 笔者用平板型PECVD设备,在典型工艺条件下淀积了薄膜,分析了高温退火对薄膜电阻率、组分、结构的影响。

The Influence of High Temperature Annealing on PECVD Titanium Silicide Films

In this paper, films of titanium silicide have been deposited by a flat-plate-type PECVD equipment. The resistivity of the film was detectd by a four-point prob. The influences of high temperature annealing on the composition and structure of the film were analysed by AES and XRD. The results show: ( 1 )the resistivity of the as-deposited titanium silicide is high and unstable, and after a high temperature annealing, the lowest resistivity is 23.8μΩ?cm; (2)the propotion of the silicon to titanium is 2.5 and 2.13, respectively, before and after annealing; ( 3 )the film is amorphous prior to annealing, and changed into a stable TiSi2 structure after a high temperature annealing.