Ultimate Control of Rate-Dependent Adhesion for Reversible Transfer Process via a Thin Elastomeric Layer.

Area of Science:

• Materials Science
• Mechanical Engineering
• Nanotechnology

Background:

• Fabricating flexible electronics relies on precise adhesion control during stamp-based transfer processes.
• Current methods offer limited control over adhesion strength, impacting transfer yield and process reliability.

Purpose of the Study:

• To develop a simple method for extending the controllable adhesion range of stamps used in flexible electronics transfer.
• To demonstrate precise device transfer by optimizing stamp adhesion properties.

Main Methods:

• Investigated the effect of elastomeric layer thickness and separation velocity on stamp adhesion.
• Utilized simple adhesion tests to design and optimize stamp properties.
• Demonstrated reversible transfer of thin silicon (Si) chips.

Main Results:

• Adhesion strength increased with decreasing elastomeric layer thickness due to confinement and rate-dependent effects.
• Extended the controllable adhesion range up to 12 times that of the bulk for a 15 μm-thick layer.
• Successfully demonstrated selective transfer and replacement of individual devices.

Conclusions:

• Adjusting elastomeric layer thickness and separation velocity offers a simple yet effective way to tune stamp adhesion.
• The proposed strategy enables precise, high-yield transfer of various materials for flexible electronics.
• This approach is applicable to a wide range of materials for selective device transfer and replacement.