PVD Target Edge Roughness Control to Reduce Arcing

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Physical vapor deposition (PVD) systems face challenges with contamination accumulation and arcing due to target edge roughness, leading to inefficient operations, increased maintenance, and wafer defects.

Innovation Solution

A PVD system design where the target edge is processed to limit the roughness extension to a specific distance, combined with a gas conducting structure for uniform gas flow, reducing contamination and arcing, and enhancing plasma stability and deposition efficiency.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If the target edge is left with natural roughness, then the manufacturing process is simpler, but contamination accumulates more on wafers and arcing increases

Engineering Contradiction:

Improvetarget processing simplicityVSAvoidcontamination accumulation and arcing

Core Design Contradiction:

Ease of manufactureVSObject-affected harmful factors

Solution Approach 1:

The target edge is processed beforehand to create a rough portion that extends only a limited distance (at most 6mm) from the first surface. This preliminary action prevents contamination and arcing issues from developing during subsequent PVD operations, as the rough edge portion is designed to minimize its extension into the deposition zone.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The target is designed with non-uniform surface characteristics: a first portion of the edge has increased surface roughness (first surface roughness) while the rest of the target maintains normal surface quality (second surface roughness). This local differentiation allows the rough portion to control contamination and arcing without affecting the overall target performance.

Inventive Principle:

Principle #3Local quality

2Object-affected harmful factors

If the rough portion of the target edge extends further from the surface, then more contaminants are trapped on the target, but the extension distance increases device complexity and maintenance requirements

Engineering Contradiction:

Improvecontaminant trapping capabilityVSAvoidtarget geometry complexity

Core Design Contradiction:

Object-affected harmful factorsVSDevice complexity

Solution Approach 1:

The invention specifies a quantitative parameter for the rough portion extension distance: at most 6 millimeters from the first surface. This parameter optimization balances the contaminant trapping capability with geometric simplicity, ensuring the rough portion is sufficient to capture contaminants but limited enough to avoid excessive complexity and maintenance needs.

Inventive Principle:

Principle #35Parameter changes

3Stability of the object's composition

If gas flow into the PVD volume is non-uniform, then the plasma stability decreases, but implementing uniform gas flow requires additional gas conducting structures

Engineering Contradiction:

Improveplasma stabilityVSAvoidgas conducting structure complexity

Core Design Contradiction:

Stability of the object's compositionVSDevice complexity

Solution Approach 1:

A gas conducting structure is introduced as an intermediary component between the gas inlet and the PVD volume. This structure facilitates uniform gas distribution throughout the deposition zone, thereby stabilizing the plasma. The intermediary enables controlled gas flow without requiring fundamental redesign of the PVD chamber.

Inventive Principle:

Principle #24Intermediary (Mediator)

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

The solution results in reduced contamination and arcing, improved operational efficiency, fewer wafer defects, and decreased maintenance requirements for the PVD system.

Implementation Method 1

A physical vapor deposition (PVD) system has a PVD chamber defining a PVD volume within which a target material of a target is deposited onto a wafer

Methodology Applied

Scientific EffectPhysical vapor deposition: Physical Vapour Deposition

Implementation Method 2

The PVD system includes a gas conducting structure in the PVD chamber to conduct the first gas into the PVD volume

Methodology Applied

Scientific EffectGas conduction: Conduction (electrical)

Data Source

PatentUS12252777B2Physical vapor deposition (PVD) system and method of processing target

Publication Date: 2025.03.18 TAIWAN SEMICONDUCTOR MANUFACTURING CO LTD

AI summary

A physical vapor deposition (PVD) system is provided. The PVD system includes a PVD chamber defining a PVD volume within which a target material of a target is deposited onto a wafer. The PVD system includes the target in the PVD chamber. The target is configured to overlie the wafer. An edge of the target extends from a first surface of the target to a second surface of the target, opposite the first surface of the target. A first portion of the edge of the target has a first surface roughness. The first portion of the edge of the target extends at most about 6 millimeters from the first surface of the target to a second portion of the edge of the target. The second portion of the edge of the target has a second surface roughness less than the first surface roughness.