Manufacturing and processing method for improving seed crystal defects of germanium single crystal

Abstract

The invention discloses a manufacturing and processing method for improving seed crystal defects of a germanium single crystal, and belongs to the field of crystal processing. The manufacturing and processing method for improving the seed crystal defects of the germanium single crystal comprises the following steps: step 1, drawing a single crystal with a proper size according to the size of a seed crystal chuck and the required size; step 2, necking a section at a taper part needing to be processed in the later period through more detailed manual control; and step 3, adopting slow shouldering, wherein the shouldering speed ranges from 10 mm/h to 15 mm/h, and the shouldering angle is larger than 45 degrees. The resistivity uniformity of the germanium seed crystal is greatly improved, the dislocation density and internal defects of the seed crystal are reduced, and a high-quality seed crystal raw material grows.

Description

technical field [0001] The invention belongs to the field of single crystal crystal production, and more specifically relates to a manufacturing and processing method for improving germanium single crystal seed crystal defects. Background technique [0002] The current manufacturing methods of round germanium seed crystals are based on the requirements of the crystal orientation, using the Czochralski method to pull a relatively large single crystal, and then cutting out a square seed crystal material with an internal circle cutting machine. Finally, the cut seed crystal material is used to roll and grind the outer circle to produce a seed crystal that needs to match the length, diameter, and seed crystal chuck. The seed crystals produced by this manufacturing method have relatively large defects. One is that due to the relatively large size of the single crystal in the process of pulling the single crystal, the uniformity of the resistivity distribution is not ideal. It i...

AI Technical Summary

Problems solved by technology

The multi-process machining process inevitably produces more processing stress, resulting in a decrease in the tensile strength of the finished seed crystal, which limits the growth length of the single crystal ingot; the multi-process machining process is difficult to ensure accurate crystal orientation, which affects the lead. Crystal quality, resulting in a decline in the crystallization rate

[0003] Disadvantages of the existing technology: in the process of pulling a single crystal, it is a relatively large single crystal, and the uniformity of resistivity is difficult to achieve an ideal state

It is difficult to achieve the ideal dislocation density and low defect during the process of pulling single crystal for seed crystal

The dislocation density and defects of the seed crystal directly cause the decrease of the crystallization rate

During the processing process, the single crystal needs to be cut in multiple directions, and more machining processes accumulate more processing stress, which has a greater impact on the tensile strength of the seed crystal.

The seed crystal is prone to breakage in the later use process, which affects the growth length of the single ingot crystal and limits the production efficiency

Multi-directional cutting and rolling processing, it is difficult to ensure the accuracy of crystal orientation, large deviation of crystal orientation will affect the seeding quality, resulting in a decrease in crystal formation rate

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