Electrical response of amorphous silicon thin-film transistors under mechanical strain

Abstract

We evaluated amorphous silicon thin-film transistors (TFTs) fabricated on polyimide foil under uniaxial compressive or tensile strain. The strain was induced by bending or stretching. The on- current and hence the electron linear mobility μ depend on strain ε as μ=μ0(1+26×ε), where tensile strain has a positive sign and the strain is parallel to the TFT source-drain current path. Upon the application of compressive or tensile strain the mobility changes “instantly” and under compression then remains constant for up to 40 h. In tension, the TFTs fail mechanically at a strain of about +0.003 but recover if the strain is released “immediately.”