Poly-Silicon TFT Metal Heat Dissipation Layer
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Poly-silicon thin film transistors on glass substries with low heat radiation properties experience characteristic fluctuations due to self-heating, leading to reliability issues in liquid crystal display devices.
Innovation Solution
A display device design where a metal layer covers at least a portion of the gate electrode, allowing for heat generated during operation to be radiated, thereby suppressing transistor characteristic fluctuations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If poly-silicon thin film transistors are formed on glass substrate with low heat radiation property, then operation speed is improved, but temperature elevation occurs due to self-heating
Solution Approach 1:
A metal layer is introduced as an intermediary heat dissipation component between the poly-silicon thin film transistor and the glass substrate. This metal layer acts as a thermal conductor to transfer heat away from the transistor, resolving the contradiction between maintaining high operation speed and preventing temperature elevation.
Solution Approach 2:
The heat dissipation function is extracted from the glass substrate (which has low heat radiation property) and assigned to a dedicated metal layer. This separation allows the substrate to maintain its structural and electrical properties while the metal layer specifically handles thermal management.
2Speed
If high gate voltage and high drain voltage are applied to improve operation performance, then operation speed is improved, but self-heating increases causing characteristic fluctuation
Solution Approach 1:
The harmful self-heating effect caused by high voltage operation is converted into a manageable thermal conduction problem. By introducing the metal layer with high thermal conductivity, the harmful heat generation is systematically conducted away, allowing high voltage operation to maintain its speed advantage while the reliability issue is resolved through thermal management.
3Temperature
If metal layer is added to improve heat radiation, then temperature control is improved, but device complexity increases
Solution Approach 1:
The metal layer serves multiple functions simultaneously: it acts as a heat sink for thermal management, can serve as an electrical connection layer, and provides structural support. This multi-functionality reduces the need for additional separate components, thereby limiting the increase in device complexity while achieving improved heat radiation.
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 design effectively prevents characteristic fluctuations in poly-silicon thin film transistors, prolonging circuit operation lifetime and enhancing product reliability by managing self-heating.
Implementation Method 1
by radiating heat which is generated when the thin film transistor is in an ON-operation state by way of the metal layer
Data Source
AI summary
A display device includes a display panel which forms a plurality of sub pixels on a substrate thereof, and a drive circuit which is configured to drive the plurality of sub pixels, wherein the drive circuit has a thin film transistor formed on the substrate, and the thin film transistor has a semiconductor layer made of poly-silicon. The thin film transistor includes: a source electrode, a semiconductor layer and a drain electrode which are formed on the substrate; a gate insulation film which is formed on the source electrode, the semiconductor layer and the drain electrode; a gate electrode which is formed on the gate insulation film and above the semiconductor layer; an insulation film which is formed on the gate electrode; and a metal layer which is formed on the insulation film in a state that the metal layer covers at least a portion of the gate electrode.