Sb-Te Alloy Sintered Target Flattened Particle Morphology

Solution Overview

Problem

The formation of Sb—Te alloy sputtering targets for phase-change recording films is hindered by particle generation, abnormal electrical discharge, and target fractures due to low density and transverse rupture strength, as well as high oxygen content, which deteriorate the quality of the thin film.

Innovation Solution

The development of an Sb—Te alloy sintered compact target using atomized powder with substantially spherical particles that are crushed and flattened, with a flatness ratio of short axis to long axis of 0.6 or less, and long axis orientation aligned within ±45°, and a reduced oxygen concentration of 1500 wtppm or less, achieved through press molding and sintering, enhancing target density and strength.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If conventional atomized powder is used for sputtering targets, then the manufacturing process is simple, but the target density and transverse rupture strength are low, causing target fractures and particle generation

Engineering Contradiction:

Improvetransverse rupture strengthVSAvoidmanufacturing process complexity

Core Design Contradiction:

StrengthVSDevice complexity

Solution Approach 1:

The invention applies preliminary action by pre-flattening the spherical atomized powder particles before sputtering deposition. This pre-processing step modifies the particle morphology to enhance packing density and structural integrity, thereby improving transverse rupture strength and preventing target fractures during operation

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The invention changes the physical parameter of the powder particles by transforming them from spherical to flattened shape. This parameter change in particle morphology directly improves the target's density and mechanical strength, resolving the contradiction between simplicity and performance

Inventive Principle:

Principle #35Parameter changes

2Manufacturing precision

If conventional sputtering targets are used, then the manufacturing cost is low, but particles and nodules are generated during sputtering, deteriorating film quality

Engineering Contradiction:

Improvefilm qualityVSAvoidmanufacturing ease

Core Design Contradiction:

Manufacturing precisionVSEase of manufacture

Solution Approach 1:

The invention applies preliminary action by pre-flattening the spherical atomized powder particles before sputtering deposition. This pre-processing step modifies the particle morphology to enhance packing density and structural integrity, thereby improving transverse rupture strength and preventing target fractures during operation

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The invention changes the physical parameter of the powder particles by transforming them from spherical to flattened shape. This parameter change in particle morphology directly improves the target's density and mechanical strength, resolving the contradiction between simplicity and performance

Inventive Principle:

Principle #35Parameter changes

3Reliability

If conventional targets with high oxygen content are used, then the manufacturing process is simple, but abnormal electrical discharge occurs during sputtering

Engineering Contradiction:

Improveelectrical discharge stabilityVSAvoidmanufacturing process complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The invention applies the inert atmosphere principle by conducting the sintering process in a controlled inert environment (vacuum or protective gas atmosphere). This prevents oxygen contamination during manufacturing, ensuring low oxygen content in the final target and eliminating abnormal electrical discharge during sputtering operation

Inventive Principle:

Principle #39Inert atmosphere (Inert environment)

Solution Approach 2:

The invention changes the chemical parameter of the target by controlling and reducing the oxygen content through inert atmosphere processing. This parameter change ensures electrical stability during sputtering while maintaining manufacturing feasibility

Inventive Principle:

Principle #35Parameter changes

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

This approach significantly reduces the generation of nodules, particles, and fractures, prevents abnormal electrical discharge, and stabilizes the phase-change recording layer, resulting in improved film quality and reduced in-plane and lot-to-lot variability.

Implementation Method 1

press molding and sintering

Methodology Applied

Scientific EffectSintering: Sintering

Data Source

PatentUS7943021B2Sb-Te alloy sintered compact target and manufacturing method thereof

Publication Date: 2011.05.17 JX NIPPON MINING & METALS CORP

AI summary

Provided is an Sb—Te alloy sintered compact target using atomized powder consisting of substantially spherical particles of an Sb—Te alloy, wherein the spherical atomized powder consists of particles that were crushed and flattened, and the flattened particles exhibiting a ratio (flatness ratio) of short axis and long axis of 0.6 or less occupy 50% or more of the overall particles. With this Sb—Te alloy sintered compact target, particles exhibiting a long axis orientation aligned within ±45° in a direction that is parallel to the target surface occupy 60% or more of the overall particles. In addition, the oxygen concentration in this Sb—Te alloy sintered compact target is 1500 wtppm or less. Thus, the Sb—Te alloy sputtering target structure can be uniformalized and refined, generation of cracks in the sintered target can be inhibited, and generation of arcing during sputtering can be inhibited. Further, surface ruggedness caused by sputter erosion can be reduced in order to obtain a high quality Sb—Te alloy sputtering target.