Transmission electron microscopy investigation of the formation of C54–TiSi2 phase on stressed (001)Si

✍ Scribed by S.L. Cheng; S.M. Chang; H.Y. Huang; L.J. Chen; C.J. Tsai

• Publisher: Elsevier Science
• Year: 2002
• Tongue: English
• Weight: 256 KB
• Volume: 33
• Category: Article
• ISSN: 0968-4328
• DOI: 10.1016/s0968-4328(02)00009-4

✦ Synopsis

The effects of stress on the formation of C54±TiSi 2 phase in Ti/(001)Si samples have been investigated by high-resolution transmission electron microscopy in conjunction with auto-correlation function (ACF) analysis. The C54±TiSi 2 phase transformation temperature in tensily stressed samples was found to be lowered by about 100 8C than that in compressively stressed samples. The thickness of amorphous interlayers (a-interlayers) between Ti metal thin ®lms and Si substrates was found to be thicker and thinner in the tensily and compressively stressed Si samples, respectively. Furthermore, the thicker a-interlayer was found to consist of a higher density of crystallites from the ACF analysis. With a higher density of crystallites in the a-interlayer, the grain size of C49±TiSi 2 was reduced since more nucleation sites are available for the formation of C49±TiSi 2 . The small grain size of C49±TiSi 2 in turn enhances the formation of C54±TiSi 2 . As a result, the phase transformation of C49± to C54±TiSi 2 is enhanced by the tensile stress present in silicon substrates.