Method and apparatus for holding and positioning semiconductor workpieces during electropolishing and/or electroplating of the workpieces

Abstract

A cell to electroplate and / or electropolish semiconductor wafers includes an electrolyte receptacle and a wafer chuck assembly. The cell also includes a first actuator configured to translate the wafer chuck assembly between a first position and a second position, where the wafer chuck assembly covers the electrolyte receptacle in the first position and retracts from the electrolyte receptacle in the second position.

Description

[0001] 1. Field of the Invention[0002] The present invention generally relates to methods and apparatus for holding and positioning semiconductor workpieces during processing of the workpieces. More particularly, the present invention relates to methods and apparatus for holding and positioning semiconductor workpieces during electroplating and / or electropolishing of semiconductor workpieces.[0003] 2. Description of the Related Art[0004] In general, semiconductor devices are manufactured or fabricated on disks of semiconducting materials called wafers or slices. More particularly, wafers are initially sliced from a silicon ingot. The wafers then undergo multiple masking, etching, and deposition processes to form the electronic circuitry of semiconductor devices.[0005] During the past decades, the semiconductor industry has increased the power of semiconductor devices in accordance with Moore's law, which predicts that the power of semiconductor devices will double every 18 months. T...

AI Technical Summary

Benefits of technology

"The present invention relates to methods and apparatus for holding and positioning semiconductor wafers during processing. More particularly, the invention is about a wafer chuck assembly for holding wafers during electroplating and electropolishing processes. The invention aims to address the increasing signal delays at interconnections on semiconductor devices caused by the increasing density of interconnections on the devices. The invention provides a solution to compensate for this issue by using copper as the metal interconnections and a wafer chuck for holding the wafers during processing. The invention also includes a flow chart for processing wafers using the wafer chuck assembly. The technical effects of the invention include reducing interconnection delay, improving chip performance, and reliability."

Problems solved by technology

However, one potential limiting factor to developing more powerful semiconductor devices is the increasing signal delays at the interconnections (the lines of conductors, which connect elements of a single semiconductor device and / or connect any number of semiconductor devices together).

However, the closer proximity of interconnections increases the line-to-line capacitance of the interconnections, which results in greater signal delay at the interconnections.

However, this approach has the disadvantage of increasing production costs associated with forming the additional layers of metal.

Furthermore, these additional layers of metal generate additional heat, which can be adverse to both chip performance and reliability.

Also, copper is less resistant to electromigration (meaning that a line formed from copper will have less tendency to thin under current load) than aluminum.

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