<title>Lattice strain in excimer-laser-crystallized poly-Si thin films</title>

Abstract

The lattice strain in excimer laser crystallized polycrystalline Si (poly-Si) thin films reflects the grain growth induced by the laser irradiation. In this report, the measurement of the lattice strain is made by using the energy-dispersive grazingincidence X-ray diffraction with synchrotron radiation. The excimer laser crystallized poly-Si thin films show tensile lattice strain in the directions parallel to the substrate surface. The { 111 } strain increases from 2.2 x iO to 5.0 x iO when the grain size increases from 40 to 200 nm. The strain is anisotropic between the { 111 } strain and the {220} strain in the layer near the substrate interface when the grain size is small. Carrier mobility in a thin film transistor tends to increase when the strain increases and the anisotropy decreases.

High-performance flexible thin-film transistors fabricated using print-transferrable polycrystalline silicon membranes on a plastic substrate

“…As the oxide undercutting progressed, the strip edges attached to the substrate, inhibiting the further expansion of the strips, and the strips became buckled. The residual stress in (thin films and) poly-Si is very common [20,21]. Large residual stress is one of the undesirable properties of poly-Si for flexible electronics applications [20,21].…”

“…The residual stress in (thin films and) poly-Si is very common [20,21]. Large residual stress is one of the undesirable properties of poly-Si for flexible electronics applications [20,21]. The non-flat topology of the released poly-Si membrane makes printing transfer impossible using the same transfer method as was used for the singlecrystal Si [17], since only a very small area can be well attached to the destination substrate (e.g.…”