@misc{9245791,
  abstract     = {{The integration of thin-film sensors onto geometrically complex industrial surfaces requires the transfer of microfabricated structures from flat donor substrates to non-planar receivers, a challenge that conventional elastomeric stamp methods cannot address at high curvature or surface roughness. This project investigates the REFLEX sugar-assisted transfer printing process as a route for integrating microfabricated K-type thin-film strain gauge structures,
consisting of patterned Chromel (K+) and Alumel (K ) alloy poles on a nickel adhesion layer, onto polished stainless steel substrates. Two donor chip variants were produced, differing in whether the nickel adhesion layer was exposed to air between deposition steps, and subjected to the full REFLEX process including sugar coating, baking, liftoff, reflow, and dissolution. Selective retrieval of the Alumel (K ) poles was demonstrated for the air-exposed variant and attributed to oxide-mediated adhesion asymmetry arising from Cr2O3 formation at the Chromel/NiO interface. Eliminating the vacuum break in the second variant resolved this asymmetry but introduced thermally induced warping of the Chromel poles during baking, which was found to be governed by the peak baking temperature rather than the heating ramp rate. Successful transfer of geometrically intact Alumel poles onto the stainless steel receiver was observed by optical microscopy, and EDS elemental mapping confirmed full retrieval of the film stack in the second variant, consistent with a cleaner and less adhesive Ni/silicon interface in the absence of a vacuum break. The results demonstrate proof of concept for REFLEX transfer of K-type thin film
structures onto stainless steel, while the challenge remains to identify baking techniques and temperature optimizations which achieve the complete transfer of the full sensor geometry.}},
  author       = {{Velaveti, Yash}},
  language     = {{eng}},
  note         = {{Student Paper}},
  title        = {{Sugar-Assisted Transfer Printing of K -Type Thin Film Strain Gauges onto Stainless Steel}},
  year         = {{2026}},
}