Chamber environment recovery method and etching method

Abstract

The invention provides a chamber environment recovery method, comprising: an oxidation step: turning on the power supply, and introducing oxygen into the reaction chamber, so as to excite the oxygen to form plasma, and the plasma reacts with the particles in the reaction chamber to pre- Evacuate the reaction chamber after a certain period of time; protective film forming step: feed the etching gas and excite to form a plasma, which etches the etched piece with the protective material to form on the inner wall of the reaction chamber Forms a protective film. The present invention also provides an etching method. The chamber environment recovery method and the etching method can not only solve the particle pollution, but also ensure the productivity and the etching rate of the subsequent etching process at the same time.

Description

technical field [0001] The invention belongs to the technical field of microelectronic processing, and in particular relates to a chamber environment restoration method. Background technique [0002] In physical vapor deposition (PVD) semiconductor process equipment, an inductively coupled (ICP) plasma generator is usually used as a precleaning (Preclean) chamber, the purpose of which is to remove contamination and impurities on the wafer surface before the process, which is beneficial to The effective implementation of the subsequent etching process ensures the integration of integrated circuits and device performance. [0003] figure 1 For a schematic diagram of an existing preclean chamber, see figure 1 , the pre-cleaning chamber includes a cavity 1, an induction coil 2, a ceramic bucket 3, a Faraday shield 4, a base 5 for placing a wafer, an upper electrode RF power supply 6, and a lower electrode RF power supply 7. Among them, the base 5 is set in the cavity 1; the F...

AI Technical Summary

Problems solved by technology

If the deposited carbonaceous material reaches a certain thickness, the particles will become loose and fall off, contaminating the wafer

For this reason, in the prior art, usually adopt the following method: after etching a certain amount (50 or 100) of wafers, it is often necessary to carry out an oxygen treatment process: feed a certain amount of oxygen into the chamber, and be excited Oxygen plasma is generated, and the particles of carbonaceous materials are oxidized to produce carbon oxides (CO / CO 2 ), and then pumped away by the molecular pump, so as to achieve the purpose of inhibiting the growth and shedding of particles; however, after the oxygen treatment process is completed, oxygen or by-products containing oxygen will remain in the chamber, which will cause further etching. The reduction of ion density is reflected in the result that the etching rate is reduced, and the general decline is 40% to 50%. For this reason, the prior art usually etches silicon dioxide SiO2 after the oxygen treatment process. 2 process to restore the chamber environment to ensure the etching rate, but this process generally takes 10 to 20 minutes to carry out the normal process, which greatly reduces the production capacity

Images