OLED TFT Stack Layout for Etch-Free NMOS Doping and PMOS Dehydrogenation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing organic light-emitting display devices face challenges in efficiently doping semiconductor layers of NMOS transistors without pre-processes and improving the dehydrogenation of PMOS transistors for enhanced driving range.
Innovation Solution
The method involves doping the semiconductor layer of an NMOS transistor with n-type impurity ions through heat treatment and improving the dehydrogenation of PMOS transistors by using a heat treatment process without etching, utilizing a stack of oxide semiconductor, insulating layers, and conductive layers to form conductive source and drain regions with reduced surface resistance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If heat treatment is used to dope semiconductor layer without pre-process, then manufacturing complexity is reduced, but doping precision may be insufficient
Solution Approach 1:
The semiconductor layer is prepared in advance with specific properties (oxide semiconductor composition, layer thickness, and structure) before the heat treatment process. This preliminary preparation ensures that when heat treatment is applied, the doping occurs precisely at desired locations (source and drain regions) without requiring additional pre-process etching steps. The pre-prepared layer structure enables self-aligned doping.
Solution Approach 2:
The heat treatment process utilizes controlled parameter changes (temperature, time, and atmospheric conditions) to achieve precise doping. By optimizing these parameters, the process achieves both simplicity (no pre-process needed) and precision (controlled dopant diffusion into specific regions of the semiconductor layer).
2Productivity
If etching process is eliminated, then manufacturing time is reduced, but doping uniformity may be compromised
Solution Approach 1:
The mechanical etching process is replaced with a thermal diffusion process. Instead of using physical/chemical etching to create patterns, the invention uses heat treatment to enable controlled diffusion of dopants. This substitution eliminates the etching step (improving productivity) while achieving uniform doping through controlled thermal processes and proper layer design.
Solution Approach 2:
The oxide semiconductor layer itself acts as an intermediary that enables uniform doping without etching. Its specific material properties and structure serve as a medium that facilitates controlled dopant diffusion, ensuring uniformity is maintained even without the etching process that would otherwise be needed to define doping regions.
3Reliability
If dehydrogenation process is improved, then transistor performance is enhanced, but process complexity increases
Solution Approach 1:
The dehydrogenation process is merged with the existing heat treatment process used for doping. By combining these two functions into a single thermal process, the invention improves transistor performance through effective dehydrogenation while avoiding the need for separate additional process steps, thus not increasing overall process complexity.
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 allows for effective doping of NMOS transistors and improved dehydrogenation of PMOS transistors, enhancing the driving range and performance of organic light-emitting display devices by simplifying the process and preventing side effects associated with etching.
Implementation Method 1
Hydrogen ions (H+) present in the second insulating layer diffuse into the first end and the second end of the oxide semiconductor
Implementation Method 2
subjecting a first end and an opposite second end of the oxide semiconductor to a reduction treatment via a heat treatment
Implementation Method 3
subjecting a first end and an opposite second end of the oxide semiconductor to a reduction treatment via a heat treatment
Data Source
AI summary
An organic light-emitting display device comprises a first thin-film transistor disposed on a substrate; and a second thin-film transistor disposed on the substrate and spaced apart from the first thin-film transistor. The first thin-film transistor comprises a first semiconductor layer, a first conductive layer disposed on the first semiconductor layer and that overlaps the first semiconductor layer, and a first insulating layer disposed between the first semiconductor layer and the first conductive layer. The second thin-film transistor comprises a second semiconductor layer, and a second conductive layer disposed on the second semiconductor layer and that overlaps the second semiconductor layer. The first semiconductor layer is disposed on a layer higher than the second semiconductor layer, the first semiconductor layer comprises an oxide semiconductor, the second semiconductor layer comprises low temperature polycrystalline silicon (LTPS), and the first insulating layer covers the entire first semiconductor layer.