Surface state of CdTe crystals irradiated by KrF excimer laser pulses near the melting threshold

✍ Scribed by V.A. Gnatyuk; T. Aoki; Y. Nakanishi; Y. Hatanaka

• Publisher: Elsevier Science
• Year: 2003
• Tongue: English
• Weight: 246 KB
• Volume: 542
• Category: Article
• ISSN: 0039-6028
• DOI: 10.1016/s0039-6028(03)00987-7

✦ Synopsis

We have studied pulsed-laser-induced melting and following crystallization of the surface of CdTe crystals subjected to irradiation with nanosecond KrF (k ¼ 248 nm) excimer laser pulses. The surface state, morphology and reconstruction of the surface layer of (1 1 1)B oriented CdTe wafers were investigated by measurements of time-resolved optical reflectivity, atomic force microscopy and reflection of high-energy electron diffraction. It was established that a jump in the reflection coefficient of a probe He-Ne beam, increase in the surface smoothness and change in the crystallinity of the surface layer occurred at the certain threshold value of laser pulse energy density W m % 50 mJ/cm 2 . The peculiarities of the laser-induced melting and transformation of the structure of CdTe surface as dependence of KrF excimer laser energy density were discussed.