AMOLED Back Plate Manufacturing via Halftone Masking
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The manufacturing of large-sized AMOLED display devices faces challenges such as complexity and high cost due to the need for multiple patterning processes and serious oxidation issues during the production of top-gate oxide AMOLED back plates, which reduce yield and increase production costs.
Innovation Solution
A method for manufacturing an AMOLED back plate is introduced, reducing the number of patterning processes from 9 to 8, involving specific steps like forming source and drain electrodes, active and gate insulating layers, and a transparent anode, while using halftone or grey tone masks to prevent oxidation by shielding metal electrodes with active and transparent conducting films.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a top-gate oxide AMOLED back plate is manufactured using conventional methods, then the device achieves high reliability and high resolution, but the manufacturing process becomes very complicated requiring 9 patterning processes
Solution Approach 1:
The patent combines multiple patterning operations into fewer steps by using a dual-tone mask that allows simultaneous formation of source/drain electrodes and gate insulating layer patterns. This merging of operations reduces the total number of patterning processes from 9 to fewer steps while maintaining the required device reliability and resolution.
Solution Approach 2:
The halftone/grey tone mask serves multiple functions simultaneously: it defines source/drain electrode patterns, gate insulating layer patterns, and via hole positions in a single exposure step. This multi-functionality reduces manufacturing complexity while producing the precise patterns needed for high-resolution reliable devices.
2Ease of manufacture
If conventional patterning processes are used to manufacture AMOLED back plate, then the device structure is formed, but serious oxidation occurs during manufacturing
Solution Approach 1:
The patent applies a protective film to metal electrodes before subsequent processing steps that could cause oxidation. This preliminary protective action prevents oxidation during manufacturing while allowing the device structure to be formed through the reduced patterning process.
Solution Approach 2:
The patent introduces a protective film as an intermediary layer between the metal electrodes and the oxidizing environment during manufacturing. This intermediary prevents direct contact between metal and oxygen, eliminating oxidation while allowing structural formation to proceed.
3Manufacturing precision
If 9 patterning processes are used to manufacture AMOLED back plate, then complete device structure is achieved, but production cost increases
Solution Approach 1:
The patent merges multiple patterning operations into fewer steps using dual-tone masks, reducing the number of expensive photolithography cycles required. This maintains complete device structure formation while significantly reducing production costs associated with repeated masking and etching operations.
Solution Approach 2:
The patent uses halftone/grey tone masks to create patterns through optical density variations rather than requiring multiple physical mask layers. This copying approach achieves the same structural completeness with fewer manufacturing steps, reducing overall production cost.
4Measurement precision
If multiple patterning processes are used, then precise device features are formed, but manufacturing time increases
Solution Approach 1:
The patent combines multiple patterning operations into single exposure steps using dual-tone masks, maintaining precise device feature formation while reducing the total number of sequential steps. This increases manufacturing speed without sacrificing the precision required for AMOLED device features.
Data Source
AI summary
The present disclosure provides an AMOLED back plate and a method for manufacturing the same. The manufacturing method includes: forming source and drain electrodes and a first via hole on a substrate having a light shielding layer and a buffer layer formed thereon, by a patterning process; depositing an active layer film and a gate insulating layer film sequentially, and forming an active layer, a gate insulating layer and a second via hole by a patterning process, wherein the active layer connected with the light shielding layer by the first via hole; forming a gate electrode and a transparent anode sequentially, wherein the transparent anode is arranged in a light emitting area and connected with one of the source and drain electrodes through the second via hole.