Growth Rates and Interface Shapes in Semiconductor Materials Using Real Time Radiographic Imaging
The success of new electronic materials has been due in part to the development of procedures that produce semiconductors of high purity and perfection. These materials have been grown from the gas phase, solution, and melts. The Bridgman technique is a way semiconductor crystals are grown from the melt. With this technique the semiconductor material is usually sealed in a fused silica ampoule, placed inside the tubular furnace, and heated to completely melt the sample. The sample solidifies by cooling the molten material in one of three ways: translating the furnace along the sample, slowly extracting the sample ampoule from the furnace, or uniformly lowering the temperature. The solidification rate is typically only a few millimeters per hour. A diagram of a typical Bridgman furnace is shown in figure 1 and more details of the furnace used in this experiment are found in the literature1. The furnaces used in such procedures are generally opaque to visible radiation.
KeywordsCrystal Length Interface Position Interface Shape Actual Growth Rate Bridgman Growth
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