View source for PDMS Mold Optimization for Robotic Stacking

= PDMS Mold Optimization for Robotic Stacking =

== Overview ==
This process describes optimization of PDMS mold fabrication for robotic stacking applications in the MonArk NSF Quantum Foundry pipeline.

The goal is to identify the optimal PDMS volume range for:
* Consistent nib formation
* Reliable mold release
* Reduced void formation
* Improved transfer reproducibility

== Applications ==
* Robotic stacking
* 2D material transfer
* PC/PDMS stamp fabrication
* Automated heterostructure assembly

== Materials ==
* PDMS mixture
* Precision balance
* Mold template
* Glass substrate
* SDS solution
* Oven curing system

== Experimental Results ==

{| class="wikitable"
! PDMS Mass (mg)
! Observation
! Result
|-
| 27
| Too shallow, poor adhesion, large voids
| Failed
|-
| 32
| Contact with glass, center voids
| Failed
|-
| 45
| Smaller voids, first nib transfer
| Partial
|-
| 50
| Consistent nib formation
| Improved
|-
| 62
| Nearly filled mold, good meniscus
| Success
|-
| 65
| Stable mold formation
| Success
|-
| 69
| Stable mold formation
| Success
|-
| 71
| Stable mold formation
| Success
|-
| 73+
| Overfilling and failed mold removal
| Failed
|}

== Key Findings ==
The optimal PDMS mass range was found to be:

'''60–70 mg'''

This range produced:
* Consistent nib formation
* Reduced void density
* Reliable mold release
* Stable meniscus formation

== Recommended Process ==
# Perform SDS pre-treatment
# Measure 60–70 mg PDMS
# Dispense PDMS into mold
# Inspect meniscus formation
# Cure mold
# Evaluate mold release quality
# Record success/failure rate

== Failure Modes ==

=== Underfilling ===
Low PDMS masses caused:
* Large voids
* Poor glass adhesion
* Incomplete nib transfer

=== Overfilling ===
High PDMS masses caused:
* Difficult mold release
* Distorted geometry
* Delamination issues

== Future Improvements ==
* Controlled oven curing
* Statistical success-rate analysis
* Optical microscopy characterization
* Automated PDMS dispensing