Lam Research Corporation

Mark Allen Kennard

Alan M Schoepp

Greg Sexton

An electrostatic chuck suitable for use at high temperatures having a replaceable expansion assembly, functioning as an outer tubulation and heat choke, between a chuck body and a heat transfer body. The expansion assembly accommodates differential thermal stresses between the chuck body and the heat transfer body, and/or limits direct heat conduction from the chuck body to the heat transfer body. The ability to operate the chuck at temperatures in excess of 200&deg; C. allows it to be used for plasma etching of materials, such as platinum, which require high temperatures to volatilize low volatility etch products as well as routine plasma etching, chemical vapor deposition, sputtering, ion implantation, ashing, etc. The novel design of the removably attached expansion assembly allows the chuck to be scaled for larger workpieces, to remain serviceable through more heating cycles, and to be economically serviced.

High temperature electrostatic chuck

A hot electrostatic chuck having an expansion joint between a chuck body and a heat transfer body. The expansion joint provides a hermetic seal, accommodates differential thermal stresses between the chuck body and the heat transfer body, and/or controls the amount of heat conducted from the chuck body to the heat transfer body. A plenum between spaced apart surfaces of the chuck body and the heat transfer body is filled with a heat transfer gas such as helium which passes through gas passages such as lift pin holes in the chuck body for backside cooling of a substrate supported on the chuck. The heat transfer gas in the plenum also conducts heat from the chuck body into the heat transfer body. The chuck body can be made of a material with desired electrical and/or thermal properties such as a metallic material or ceramic material. The chuck can be used in various semiconductor processes such as plasma etching, chemical vapor deposition, sputtering, ion implantation, ashing, etc. The ability to operate the chuck at temperatures in excess of 200&deg; C. allows it to be used for plasma etching of noble metals such as Pt which require etching at high temperatures to volatilize low volatility etch products.

A method for etching a trench in a monocrystal silicon layer. The method includes providing a plasma processing system having a plasma processing chamber. The plasma processing system has a variable plasma generation source and a variable ion energy source with the variable plasma generation source being configured to be controlled independently of the variable ion energy source. The method further includes flowing an etchant source gas that includes O.sub.2, helium, and at least one of SF.sub.6 and NF.sub.3 into the plasma processing chamber. There is also included energizing both the variable plasma generation source and the variable ion energy source to form a plasma from the etchant source gas. Additionally, there is included employing the plasma to etch the trench.

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Pleasanton, CA, United States of America

Mark Allen Kennard