Gas supply system and gas supply method of ion source

Abstract

The invention provides a gas supply system and a gas supply method of an ion source. The gas supply system comprises a reaction cavity, a first heating device, a flow controller and a gas pipeline; the reaction cavity is used for placing a solid source; one end of the gas pipeline is connected with the reaction cavity, and the other end of the gas pipeline is connected with the ion source; and the first heating device is arranged on the reaction cavity and used for heating the solid source to a preset temperature so that the solid source can be gasified, and gas obtained after the solid source is gasified flows out of the reaction cavity and enters the ion source through the gas pipeline. The gas supply system can heat and gasify the solid source and provide stable gas flow for the ion source, so that the uniformity of ion implantation on the surface of a wafer is ensured, the productivity of ion implantation of the wafer is improved, and meanwhile, the maintenance period of the ion source is prolonged.

Description

technical field [0001] The invention relates to the technical field of semiconductor manufacturing, in particular to a gas supply system and a gas supply method for an ion source. Background technique [0002] Ion implanter is a key equipment in the manufacturing process of integrated circuits. Ion implantation is a technique for doping the area near the surface of the semiconductor wafer. The purpose is to change the carrier concentration and conductivity type of the semiconductor. During ion implantation, the gas source to be injected needs to be introduced into the electric field of the ion source, and be ionized into ions in the electric field of the ion source. If the substance to be injected is a solid source, it needs to be heated and vaporized to make it into a gas phase before being introduced into the ion source. [0003] Existing ion implanters generally adopt the method of loading a solid source into the ion source, and introducing gas in a manner of gasifying t...

AI Technical Summary

Problems solved by technology

For the gas introduced in this way, since the heating temperature and pressure of the solid source placed in the ion source cannot be precisely controlled, and the remaining solid amount of the solid source gradually decreases as the gasification proceeds, the gas flow rate generated by the gasification of the solid source Very unstable, which causes the ion beam during ion implantation to be very unstable, which in turn affects the uniformity of implanted ions on the wafer surface

Furthermore, due to the limited loading capacity of the ion source, it can only accommodate a small number of solid sources. After a small amount of solid source is gasified, the ion source needs to be maintained, which greatly shortens the maintenance cycle of the ion source and increases the number of operators. operating frequency and reduce the lifetime of the ion source

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