Oxide TFT Gate Stack With Al2O3 Covering for Oxidation Reliability

Solution Overview

Problem

In display devices using thin film transistors with oxide semiconductors, oxidation failures due to cracks or holes in aluminum oxide films can lead to display failures and reduced yields.

Innovation Solution

A semiconductor device configuration that includes a thin film transistor with an oxide semiconductor, where an aluminum oxide film is covered by a third insulating film to prevent oxygen emission and ensure sufficient oxidation of the channel region.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If an aluminum oxide film is used to oxidize the oxide semiconductor, then the oxidation effect is improved, but the film may crack or form holes due to foreign substances, causing oxygen to escape and oxidation to fail

Engineering Contradiction:

Improveoxidation reliabilityVSAvoidforeign substance contamination

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

A protective film is formed over the aluminum oxide film before the oxidation process to prevent foreign substance contamination. This preliminary protective action ensures that even if the aluminum oxide film cracks or forms holes, the oxygen supply to the oxide semiconductor is not compromised, thereby preventing oxidation failure.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The protective film acts as a cushioning layer that compensates for potential defects in the aluminum oxide film. By providing this beforehand cushioning, the system ensures continuous oxygen supply to the oxide semiconductor even when the aluminum oxide film is compromised by cracks or holes caused by foreign substances.

Inventive Principle:

Principle #11Beforehand cushioning (Prior cushioning)

2Device complexity

If the aluminum oxide film is made thinner to reduce manufacturing complexity, then the device complexity is reduced, but the film becomes more susceptible to cracking and hole formation

Engineering Contradiction:

Improvefilm structure complexityVSAvoidfilm integrity

Core Design Contradiction:

Device complexityVSReliability

Solution Approach 1:

A protective film is formed over the aluminum oxide film before the oxidation process to prevent foreign substance contamination. This preliminary protective action ensures that even if the aluminum oxide film cracks or forms holes, the oxygen supply to the oxide semiconductor is not compromised, thereby preventing oxidation failure.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The protective film acts as a cushioning layer that compensates for potential defects in the aluminum oxide film. By providing this beforehand cushioning, the system ensures continuous oxygen supply to the oxide semiconductor even when the aluminum oxide film is compromised by cracks or holes caused by foreign substances.

Inventive Principle:

Principle #11Beforehand cushioning (Prior cushioning)

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 configuration enhances the transistor properties of the oxide semiconductor thin film transistors, reducing display failures and improving the yield of display devices.

Implementation Method 1

oxygen injected into a gate insulating film is dissipated

Methodology Applied

Scientific EffectDiffusion: Diffusion

Implementation Method 2

oxygen injected into a gate insulating film is dissipated, and the oxidation of the oxide semiconductor as an active layer sometimes fails

Methodology Applied

Scientific EffectOxygen emission:

Data Source

PatentUS12272696B2Oxide semiconductor device

Publication Date: 2025.04.08 MAGNOLIA WHITE CORP

AI summary

There is provided a technique that enables a reduction in the display failure of a display device and the improvement of the yields of the display device in a display device that adopts a semiconductor device including a thin film transistor using an oxide semiconductor. A semiconductor device according to an embodiment includes a thin film transistor having an oxide semiconductor. The oxide semiconductor has a drain region, a source region, and a channel region provided between the drain region and the source region. The thin film transistor includes a gate insulating film provided on the channel region, an aluminum oxide film provided on the gate insulating film, an insulating film provided on the aluminum oxide film, and a gate electrode provided on the insulating film.