A semiconductor device and method of forming the same

Abstract

The invention provides a semiconductor device, which comprises a semiconductor substrate, source and drain regions and grids, wherein the semiconductor substrate is positioned on an insulation layer; the source and drain regions are connected with first opposite side faces of the semiconductor substrate; the grids are positioned on second opposite side faces of the semiconductor substrate; the semiconductor substrate is provided with a hollow cavity; and the insulation layer is exposed out of the hollow cavity. A formation method of the semiconductor device comprises the following steps of: forming the semiconductor substrate on the insulation layer; forming the source and drain regions which are connected with the first opposite side faces of the semiconductor substrate; forming the grids which are positioned on the second opposite side faces of the semiconductor substrate; removing partial materials from the semiconductor substrate to form the hollow cavity in the semiconductor substrate, wherein the insulation layer is exposed from the hollow cavity. By the semiconductor device and the formation method thereof, a short channel effect, resistance of the source and drain regions and parasitic capacitance can be reduced.

Description

technical field [0001] The present invention relates to the technical field of semiconductors, in particular to a semiconductor device and a forming method thereof. Background technique [0002] As the channel length of MOSFET (Metal Oxide Field Effect Transistor) continues to shorten, a series of effects that can be ignored in the MOSFET long channel model become more and more significant, and even become the dominant factor affecting performance. This phenomenon is collectively referred to as short channeling effect. The short channel effect is easy to deteriorate the electrical performance of the device, such as causing a decrease in the gate threshold voltage, an increase in power consumption, and a decrease in the signal-to-noise ratio. [0003] In order to control the short channel effect, people have to dope more impurity elements such as phosphorus and boron into the channel, but this will easily lead to the decrease of carrier mobility in the channel of the device;...

AI Technical Summary

Problems solved by technology

Thus, as the width (d) of the source-drain region 30 increases, the parasitic capacitance between the source-drain region 30 and the gate 40 and the semiconductor base 20 increases, thus increasing the resistance capacitance Delay or degrade device AC performance

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