Display Module LED Relay Transfer for Seam-Free Array Stretching

Solution Overview

Problem

Existing display modules using LEDs face performance variations due to manufacturing tolerances, leading to uneven color and brightness across the wafer, and the formation of seams and periodic patterns in large format displays.

Innovation Solution

A method involving multiple relay substrates is used to transport LEDs with maintained gaps, stretching the array in both row and column directions to minimize processable gaps and ensure uniform distribution on a target substrate, preventing seams and patterns.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If LEDs are distributed in one area of the wafer (e.g., center part), then manufacturing precision is improved, but productivity deteriorates due to limited number of usable LEDs

Engineering Contradiction:

ImproveLED performance uniformityVSAvoidnumber of LED chips per epi substrate

Core Design Contradiction:

Manufacturing precisionVSProductivity

Solution Approach 1:

The epi substrate is divided into multiple regions with different LED pitch configurations. A first region contains LEDs at a first pitch suitable for high precision, while a second region contains LEDs at a second pitch for increased density. This segmentation allows different areas to serve different functional requirements simultaneously.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different regions of the epi substrate are assigned different LED pitches based on local requirements. The first region uses a larger pitch for better performance uniformity, while the second region uses a smaller pitch to maximize the number of LEDs. Each region's quality characteristics are optimized for its specific purpose.

Inventive Principle:

Principle #3Local quality

2Productivity

If LEDs are arrayed with minimum processable gaps to maximize density, then productivity is improved, but manufacturing precision deteriorates due to performance variations

Engineering Contradiction:

Improvenumber of LED chips per epi substrateVSAvoidLED performance uniformity

Core Design Contradiction:

ProductivityVSManufacturing precision

Solution Approach 1:

The epi substrate is divided into multiple regions with different LED pitch configurations. A first region contains LEDs at a first pitch suitable for high precision, while a second region contains LEDs at a second pitch for increased density. This segmentation allows different areas to serve different functional requirements simultaneously.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different regions of the epi substrate are assigned different LED pitches based on local requirements. The first region uses a larger pitch for better performance uniformity, while the second region uses a smaller pitch to maximize the number of LEDs. Each region's quality characteristics are optimized for its specific purpose.

Inventive Principle:

Principle #3Local quality

3Device complexity

If LEDs are transferred directly from substrate to target substrate, then device complexity is reduced, but manufacturing precision deteriorates due to periodic patterns and seams

Engineering Contradiction:

Improvenumber of relay substratesVSAvoidLED array uniformity

Core Design Contradiction:

Device complexityVSManufacturing precision

Solution Approach 1:

A relay substrate is introduced as an intermediary between the epi substrate and the target substrate. The relay substrate receives LEDs from the epi substrate and then transfers them to the target substrate. This intermediate step allows for proper array formation and prevents direct transfer issues.

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The relay substrate is prepared in advance with the appropriate array configuration before receiving LEDs from the epi substrate. This preliminary preparation ensures that when LEDs are transferred, they are properly positioned and spaced, preventing periodic patterns and seams in the final display.

Inventive Principle:

Principle #10Preliminary action

Data Source

PatentUS20260040739A1Display module and method for manufacturing display module

Publication Date: 2026.02.05 SAMSUNG ELECTRONICS CO LTD

AI summary

A method for manufacturing a display module includes the steps of: transferring LEDs of a substrate to a first relay substrate; transferring the LEDs of the first relay substrate to a second relay substrate in a primary stretch array such that a gap between adjacent LEDs on the second relay substrate is greater than a gap between adjacent LEDs on the first relay substrate in one direction from among a row direction and a column direction; and transferring the LEDs of the second relay substrate to a target substrate in a secondary stretch array such that a gap between adjacent LEDs on the target substrate is greater than a gap between adjacent LEDs on the second relay substrate in a remaining direction from among the row direction and the column direction.