Papers by Keyword: Growth Striations

Abstract: The axial distribution of electrical and optical properties of a 4 inch Czochralski-grown silicon single crystal were analyzed by different methods that can be applied in the scanning mode. These methods were tested with respect to the suitability to reveal growth striations. The residual stress was visualized by SIRIS (Scanning Infrared Stress Inspection System) and SIREX (Scanning Infrared Stress Explorer), the electrical resistivity by LPS (Lateral Photovoltage Scanning) and SRP (Spreading Resistance Profiling), and the lifetime of the minority charge carriers by MDP (Microwave Detected Photoconductivity) mapping. The concentration of interstitial oxygen (O_i) across the growth striations was determined by FTIR (Fourier Transform Infrared) spectroscopy. We demonstrate for the first time on the micrometer scale that the O_i scan is very well-correlated with the profile of Δσ (difference of the in-plane principal stress components). The stress field is tensile oriented in growth direction, i. e. perpendicularly to the growth striations. The stress-concentration coefficient has been estimated to be in the order of 10^-13 Pa cm^-3 what does agree well with previous XRD results.

Abstract: As a preliminary experiment for the growth of InGaSb alloy crystals under microgravity at International Space Station (ISS), bulk crystal was grown under terrestrial condition using the same gradient heating furnace (GHF). Czochralski grown GaSb <111>B single crystal was used as a seed and feed crystals for the growth of InGaSb bulk crystals. During the growth, heat pulses were intentionally introduced periodically to create the growth striations. From the striations, the growth rate of the grown crystal was estimated. The results show that the growth rate was gradually increased from the beginning of the growth and became stable. On the other hand the In composition of the grown crystal decreased along the growth direction. From the In composition, the temperature gradient in the solution was estimated and it was almost the same of that fixed during the growth.