Deformation‐induced stress/strain mapping and performance evaluation of a‐IGZO thin‐film transistors for flexible electronic applications

Abstract

In the flexible electronics sector, there is an urgent need for higher performance, and hence, many new technologies are emerging in recent years. The field of organic and printed electronics allows low production costs and large areas. The silicon technology allows nanometric resolutions and better performance. A new technology CAD (TCAD)‐based design methodology is needed to combine both mechanical flexibility and high performance. This work presents a predictive TCAD calibration methodology for indium‐gallium‐zinc‐oxide thin‐film transistors (TFTs), employing physics‐based modeling to support and enhance simulation‐based device development. In this work, based on the nonlinear finite element technique, a TCAD framework has been developed to introduce different types of large deformations and obtain the local stress/strain profiles (mapping) inside the devices. The impacts of various kinds of deformations on the electrical characteristics of the strained TFTs are studied. The feasibility (via predictions) for amorphous‐indium‐gallium‐zinc‐oxide (a‐IGZO) TFTs, combining considerable mechanical flexibility, high electrical performance, and finally, excellent stability under deformation, may be useful for mechanical deformation‐aware design and modeling for highly flexible electronics. To the best of our knowledge, the highest cutoff frequency (fT > 690 MHz) possible for strain‐engineered a‐IGZO TFTs is predicted in entirely flexible technologies that can be used to realize active transceivers operating in the MHz regime.

A Brief Review on Flexible Electronics for IoT: Solutions for Sustainability and New Perspectives for Designers

“…In addition to efforts to integrate flexible device models into SPICE, other studies have been done to simulate the mechanical deformations of devices and the related variation of electrical properties. In [251] both the biaxial and uniaxial bending stresses in polysilicon TFTs using process conditions like thermal mismatch among materials have been modeled, in [252] a framework based on the nonlinear finite element technique for obtaining stress/strain mapping from the deformation gradient for isotropic materials is developed, that in [253] has been applied to flexible electronics application. In [254] a simulation approach for evaluating the performance of arbitrarily deformed flexible electronic components is presented, that exploits a computer graphic method for three-dimensional object manipulation.…”

Computing-in-memory with thin-filmtransistors: challenges and opportunities

“…For cut-off frequency (f T ) that indicates the maximum speed of the device, TFTs are still orders of magnitudes lower than CMOS. For advanced devices, f T = 63.6 GHz is reported for p-Si TFT [48], 690 MHz for flexible IGZO TFT [49], 20 MHz for flexible organic TFT [50], while the sub 5 nm node CMOS could have 400 GHz [51]. f T of a field-effect transistor at the saturation region can be roughly characterized as follows [50]:…”