Tunneling field effect transistor and forming method thereof

Abstract

The invention provides a tunneling field effect transistor comprising a semiconductor substrate, first gates, second gates, first doped regions, and second doped regions. Fins are formed on the semiconductor substrate. Each first gate and the corresponding second gate are respectively formed on the semiconductor substrate at the two sides of the corresponding fin. A gate dielectric layer is formed among each first gate, a first side of the corresponding fin and the semiconductor substrate, and a gate dielectric layer is formed among each second gate, a second side of the corresponding fin and the semiconductor substrate. The first doped regions and the second doped regions are respectively disposed in the semiconductor substrate at one side of the first gates and at one side of the second gates. A narrow tunneling junction is realized by controlling the width of the fins, the tunneling current is increased, and the conduction current is further improved by increasing the effective tunneling area. In addition, defect-related leakage current can be inhibited, and the sub threshold characteristic of devices can be improved.

Description

technical field [0001] The invention relates to the field of semiconductor devices, in particular to a tunneling field effect transistor and a forming method thereof. Background technique [0002] With the continuous shrinking of the device size, the number of devices per unit area of ​​the chip is increasing, and how to reduce power consumption has become an increasingly prominent problem. [0003] The structure of a conventional tunneling field effect transistor (conventional-TFET) mainly includes a substrate (channel), a gate dielectric layer, a gate, and source / drain regions on both sides of the gate. It mainly works based on the quantum tunneling effect. Taking the P-type tunneling field effect transistor as an example, a negative voltage is applied to the gate, the potential of the channel region rises, quantum tunneling occurs from the source region to the channel region, and the electrons and holes generated by the tunneling pass from the source region to the channel...

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Problems solved by technology

However, in order to reduce the sub-threshold swing and increase the conduction current, the tunneling junction needs to be as narrow as possible. However, the tunneling field effect transistor with the existing structure will always cause the diffusion distribution of impurities during the injection and heat treatment process, and it is difficult to achieve a narrow tunneling junction. tunneling junction

[0005] In addition, in conventional tunneling field effect transistors, the source and drain regions are highly doped, and the doping will inevitably introduce defects, and the leakage current associated with these defects will destroy the reduction of the subthreshold swing.

Moreover, conventional tunneling field effect transistors have bipolar characteristics that can be turned on at both positive and negative gate voltages, making it difficult to completely turn off the device

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