| 摘要 |
PURPOSE:To control accurately the shoulder of a single crystal to a prescribed shape by installing a device for detecting the diameter of a single crystal and a signal generator and by setting the temp. of a crucible for growing a single crystal from a melt with specified signals. CONSTITUTION:Polycrystalline InSb as a starting material is put in a crucible 3 and melted by heating. A seed crystal is brought into contact with the melt 4, and it is pulled up while rotating to form the neck of a crystal. The temp. of the melt 4 is then lowered by about 1 deg.C. The crystal thickens slowly and forms a shoulder. The output of a standard weight signal generator 8 is set beforehand so that the shoulder is spread at 30 deg. angle, and a regulator 9 is brought into action to start the control of the diameter of the shoulder. At the same time, a switch 13 is shut to bring a signal generator 10 into action. The temp. of the crucible 3 is controlled with generated signals proportional to the square of the detected diameter, and pulling is continued until the crystal attains the prescribed diameter. When the crystal attains the prescribed diameter, the switch 13 is opened to stop the action of the generator 10, and the body of the crystal is grown under instructions from the regulator 9. |
