Electrochromic Device Laser Scribing Reduces Leakage

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Solid-state electrochromic devices face issues with intrinsic electronic leakage, which leads to compromised performance, including reduced dynamic range, non-uniform coloration, decreased ionic conductance, and increased power consumption, due to electronic breakdown and dust contamination during vacuum cycling in the deposition process.

Innovation Solution

The electrochromic device employs an improved insulating film structure with a single laser processing step between two coating processes, separating the electrochromic and ion conductor layers to minimize vacuum cycling and reduce electronic leakage, using a method that includes scribing the lower transparent conductor layer and ion conductor layer to create isolated regions, and optionally incorporating additional buffer layers for enhanced separation between conductive layers.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the ion conductor layer is made thicker to reduce electronic leakage, then electronic leakage is reduced, but optical properties are degraded and deposition time increases

Engineering Contradiction:
Improveelectronic leakage reductionVSAvoiddeposition time
Core Design Contradiction:
ReliabilityVSProductivity

Solution Approach 1:

The patent divides the ion conductor layer into multiple discrete layers (first ion conductor layer, second ion conductor layer, third ion conductor layer) rather than using a single thick layer. This segmentation allows the total thickness to be reduced while maintaining effective leakage blocking through the combined barrier effect of multiple layers, thus reducing deposition time while preventing electronic leakage.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent uses composite material structures by combining different ion conductor layers with distinct functional characteristics. The first layer provides initial protection, the second layer (with laser cuts) provides enhanced leakage blocking, and the third layer completes the barrier. This composite approach achieves superior leakage prevention with reduced total thickness compared to a single thick layer, maintaining optical properties while reducing deposition time.

Inventive Principle:
Principle #40Composite materials

2Manufacturing precision

If vacuum cycling is increased to improve coating quality, then coating precision is improved, but dust contamination increases and yield decreases

Engineering Contradiction:
Improvecoating qualityVSAvoidyield
Core Design Contradiction:
Manufacturing precisionVSProductivity

Solution Approach 1:

The patent performs laser cutting of the second ion conductor layer before depositing the third ion conductor layer and subsequent electrochromic layers. This preliminary action creates isolated regions that prevent dust contamination from affecting subsequent layers during vacuum cycling, thereby maintaining coating quality while reducing the need for repeated vacuum cycles and improving yield.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

By segmenting the ion conductor layer into multiple layers with laser cuts between them, the patent creates isolated deposition zones. This allows each layer to be deposited with minimal dust contamination from previous vacuum cycling operations, improving coating precision while reducing the total number of vacuum cycles required and increasing overall yield.

Inventive Principle:
Principle #1Segmentation

3Reliability

If laser scribing is performed in vacuum system, then electrical isolation is achieved, but focus precision deteriorates due to mechanical tolerances

Engineering Contradiction:
Improveelectrical isolationVSAvoidlaser focus precision
Core Design Contradiction:
ReliabilityVSManufacturing precision

Solution Approach 1:

The patent performs laser cutting after vacuum deposition rather than during vacuum deposition. This dimensional change in the process sequence allows the laser system to operate in atmospheric conditions where focus precision is not compromised by vacuum mechanical tolerances, while still achieving the required electrical isolation through the laser-cut patterns in the ion conductor layers.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

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 increases yield and facilitates mass production by reducing electronic leakage, maintaining optimal performance while minimizing the thickness of ion conductor layers, thus avoiding degraded optical properties and increased layer deposition time and cost.

Implementation Method 1

it is necessary to maintain an extremely tight focus for the laser. Such focus is very difficult to achieve efficiently with the mechanical tolerances present in the system.

Methodology Applied
Scientific EffectLaser ablation: Laser Ablation

Implementation Method 2

electrochromic devices employ materials capable of reversibly altering their optical properties following electrochemical oxidation and reduction in response to an applied potential

Methodology Applied
Scientific EffectElectrochromism: Electrochromism

Implementation Method 3

an ion conductor layer ('IC') 13 which functionally replaces an electrolyte, allowing the passage of ions while blocking electronic current

Methodology Applied
Scientific EffectIon conduction: Fast Ion Conductor

Data Source

PatentEP2965150B1Electrochromic device with laser cuts to reduce electrical leakage
Publication Date: 2019.06.19 SAGE ELECTROCHROMICS INC
  • EP2965150B1 patent drawingFigure 1~2
  • EP2965150B1 patent drawingFigure 3~4
  • EP2965150B1 patent drawingFigure 5~7

AI summary

One object of the present invention is to provide an electrochromic device (70) having improved insulating film structure to reduce electrical leakage. The improved structure includes a lower conductive layer (75), upper conductive layer (71), an electrochromic electrode layer (74a,b), a counter electrode layer (72), and at least one ion conductor layer (73a,b, 77) sandwiched between the electrochromic electrode layer and the counter electrode layer. The lower conductive layer and the electrochromic electrode layer are scribed and the gap (P1) formed from the scribing is filled with the layers formed above the electrochromic electrode layer. In some aspects, the ion conductor layer is also scribed with the lower conductor and electrochromic electrode layers and the gap formed from the scribing is filled with the layers formed above the ion conductor layer. In further aspects, the insulating film may include one or more buffer layers (76) formed above an ion conductor layer, further separating the upper conductive layer from the lower conductive layer.