摘要(英) |
As the size of the ingot grows larger, the uneven thicknese difference on the surface of the wafer becomes more and more obvious after wire-sawing. The unevenness of the wafer surface will not only increase the cost of the subsequent semiconductor manufacturing process, but also waste more materials. In the case of slow crystal growth and increasing demand for wafers, how to reduce the waste of materials and the cost increase of subsequent processes is an important challenge. We think that there are two reasons for affecting the flatness of wafers in wire sawing: First, the ingot is heated differently at different depths during wire sawing results in different thermal expansion of the ingot, causing the difference height of the wafer surface after cutting. Second, the vibration of the wire during cutting makes the surface of the wafer uneven. We preliminarily think that the difference in heating of ingots with different depths during cutting is the main reason for the uneven surface. The vibration of the wire will cause local surface unevenness. This research will focus on the first reason.
In this study, a model with a thicknese of 300 mm and a thicknese of 180 mm are established to study the influence of cutting heat, and the temperature obtained by the numerical simulation is compared with the experimental data, and the heat absorption ratio of the crystal ingot and the slurry will be obtained. Then, discussing how to change the wire drawing speed at each depth to make the temperatures obtained at different depths the same, so that the flatness of the wafer surface can be improved. |
參考文獻 |
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