Quartz crucible and crystal pulling furnace

Abstract

The embodiment of the invention discloses a quartz crucible for drawing a crystal bar. The quartz crucible comprises a crucible substrate made of a silicon dioxide material and a plating film plated on a part of the inner surface of the crucible substrate, wherein the plating film is used for preventing oxygen atoms of the plated part of the crucible substrate from being separated out in the process of drawing a crystal bar, and the plating area of the plating film is gradually reduced in the direction from the opening part of the crucible substrate to the bottom of the crucible substrate. Due to the existence of the plating film, the contact area of a melt and the quartz crucible is reduced, so that the oxygen content of the drawn silicon single crystal bar is more uniform.

Description

technical field [0001] The invention relates to the field of semiconductor silicon wafer production, in particular to a quartz crucible and a crystal pulling furnace. Background technique [0002] Silicon wafers used to produce semiconductor electronic components such as integrated circuits are mainly manufactured by slicing single crystal silicon rods drawn by the Czochralski method. The Czochralski method involves melting polysilicon from a crucible assembly to obtain a silicon melt, immersing a single crystal seed in the silicon melt, and continuously elevating the seed to move away from the surface of the silicon melt, thereby moving in phase A single crystal silicon rod grows at the interface. When dopants are added, the melting of polycrystalline silicon is also accompanied by the dissolution of dopants. As the single crystal silicon rods continue to grow, the melt in the quartz crucible also continues to decline. When the single crystal silicon rods are drawn, Only ...

AI Technical Summary

Problems solved by technology

However, the oxygen content in single crystal silicon rods is not uniform and tends to be high at the head and low at the end. The reason for this is that the segregation coefficient of oxygen is approximately equal to 1 and thus the distribution in the solid and the melt is almost the same , but with the continuous decline of the melt in the crucible during the crystal pulling process, the contact area between the melt and the quartz crucible gradually decreases, so the oxygen precipitated from the inner surface of the quartz crucible during the crystal pulling process cannot be evenly distributed in the molten In the body, the oxygen concentration in the drawn single crystal silicon rod will also be uneven, and there is a situation that the oxygen distribution in the single crystal silicon rod is high at the head and low at the end. The uniformity of Bulk Micro Defect (BMD) affects

Images