Fixtureless vertical paddle electroplating cell

Abstract

A submersible assembly for exposing respective front surfaces of different work-pieces to an electroplating bath as a partial respective electrodes thereof, while protecting opposing, rear surfaces of the work-pieces from the bath. The assembly includes a wall, having a front surface also partially forming a first electrode of the bath, and having an opening smaller in size than the perimeter of a work-piece while substantially corresponding in size to the portion of the front surface of the work-piece to be exposed to the bath. The assembly also includes a chuck mechanism for applying pressure against the rear surface of the work-piece to thereby hold the work-piece against a rear surface of the wall and create a fluid-tight seal between the rear surface of the wall and the perimeter of the front surface of the work-piece, thereby exposing the front surface of the work-piece to the bath while protecting the rear surface of the work-piece from exposure to the bath.

Description

TECHNICAL FIELD [0001] The present invention relates in general to electroplating a work-piece such as a silicon, integrated circuit wafer. More particularly, the present invention relates to a technique which allows easy insertion, positioning, and removal of a work-piece from an electroplating cell. BACKGROUND OF THE INVENTION [0002] Electroplating is a common process for depositing a thin film of metal or alloy on a work-piece such as a silicon wafer. During the electroplating process, the work-piece is placed in a suitable electrolyte bath (in a “plating cell”) containing ions of the metal to be deposited. The work-piece forms a first electrode (e.g., cathode) connected to the negative terminal of a power supply. A separate electrode (e.g., anode) separately positioned in the bath is connected to the positive terminal of the power supply. The anode and cathode are electrically charged to create an electric potential or field through the electrolyte. This electric field drives th...

AI Technical Summary

Benefits of technology

[0007] The assembly also includes a chuck mechanism for applying pressure against the rear surface of the work-piece to thereby hold the work-piece against a rear surface of the wall and create a fluid-tight seal between the rear surface of the wall and the perimeter of the front surface of the work-piece, thereby exposing the front surface of the work-piece to the bath while protecting the rear surface of the work-piece from exposure to the bath.

[0010] The retractable, bellow-sealed chuck; the wall / cathode contact with recess seal; and the overall submersible cathode compartment assembly are the operative elements of the vertical paddle plating cell of the present invention. This unique combination eliminates the need for complicated, manually assembled fixturing. The elimination of manually assembled fixturing enables the present invention to be very well suited for automated loading and unloading of a work-piece (e.g., an integrated circuit wafer), immediately from / to adjacent process steps, thus increasing production throughput.

Problems solved by technology

Certain challenges exist in electroplating systems.

In addition, some systems require the use of complex fixtures to hold the work-piece in place during electroplating.

This technique has certain drawbacks—including the need to assemble and disassemble the PVDF holder—resulting in decreased production throughput.

Images