Single reactor, multi-pressure chemical vapor deposition for semiconductor devices

Abstract

An apparatus and method for forming at least a portion of an electronic device include a High Vacuum-Chemical Vapor Deposition (UHV-CVD) system and a Low Pressure-Chemical Vapor Deposition (LPCVD) system using a common reactor. The invention overcomes the problem, of silicon containing wafers being dipped in HF acid prior to CVD processing, and the problem of surface passivation between processes in multiple CVD reactors.

Description

FIELD OF THE INVENTION [0001] This invention relates to semiconductor process equipment and methods, and more particularly, to Chemical Vapor Deposition (CVD) apparatuses and methods for performing a plurality of in situ processes for forming all or portions of an electronic device. BACKGROUND OF THE INVENTION [0002] Present Chemical Vapor Deposition Equipment consists of multiple chambers, gas inlets, gas outlets, vacuum pumps and transfer load-lock systems for inserting, for example, semiconductor wafers into the chambers. Examples of Chemical Vapor Deposition Equipment are described in U.S. Pat. No. 5,259,918 issued on Nov. 9, 1993, which shows an Ultra High Vacuum Chemical Vapor Deposition (UHV-CVD) reactor with a vacuum loading chamber; and in U.S. Pat. No. 6,013,134 issued on Jan. 11, 2000, which shows a UHV transfer system for transferring wafers between a UHV-CVD reactor and a Low Pressure-Chemical Vapor Deposition (LPCVD) reactor. The entire contents of both of these patent...

AI Technical Summary

Benefits of technology

The present invention provides an apparatus and method for improving the productivity of a UHV-CVD system by combining the UHV-CVD and LPCVD processes in a single reactor. The apparatus includes an AICVD system with a single reaction chamber that can operate in vacuum, low pressure, and ultra high vacuum. The method includes a low mass, rapid heating furnace with three pumping packages and a cryopump for vacuum transfer. The invention also provides precise control of transitions from LPCVD to UHV-CVD processes to prevent formation of deleterious defects and improve the quality of the epitaxial film. The use of a cryopump allows for seamless transitions between different vacuum pressures and prevents oxidation of the Si surface. The invention also provides methods for prebanking a silicon substrate surface, growing a silicon containing layer, and continuous epitaxial growth on a semiconductor substrate in a single reactor.

Problems solved by technology

Although it is possible to transition from LPCVD to UHV-CVD without the cryopump, the environment would be contaminated with residual species from the LPCVD process which are not efficiently removed by a turbomolecular pump The cryopump is proficient at removing H2O, O2, B, As, P, and other species that otherwise could accumulate on the Si surface, react with the Si surface or otherwise degrade the quality or prevent formation of the subsequent epitaxial film.

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