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arXiv · 1711.01832

Switching Mechanism and the Scalability of vertical-TFETs

Fan Chen·Hesameddin Ilatikhameneh·Yaohua Tan·Gerhard Klimeck·Rajib Rahman
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Abstract

In this work, vertical tunnel field-effect transistors (v-TFETs) based on vertically stacked heretojunctions from 2D transition metal dichalcogenide (TMD) materials are studied by atomistic quantum transport simulations. The switching mechanism of v-TFET is found to be different from previous predictions. As a consequence of this switching mechanism, the extension region, where the materials are not stacked over is found to be critical for turning off the v-TFET. This extension region makes the scaling of v-TFETs challenging. In addition, due to the presence of both positive and negative charges inside the channel, v-TFETs also exhibit negative capacitance. As a result, v-TFETs have good energy-delay products and are one of the promising candidates for low power applications.

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Fan Chen, Hesameddin Ilatikhameneh, Yaohua Tan, Gerhard Klimeck, Rajib Rahman. 2017-11-06. Switching Mechanism and the Scalability of vertical-TFETs. https://doi.org/10.1109/ted.2018.2831688

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