Silicon-on-insulator radio frequency switch device and manufacturing method thereof

Abstract

The invention provides a silicon-on-insulator radio frequency switch device and a manufacturing method thereof. The method comprises the steps of: forming a first oxide layer, a first monocrystallinesilicon layer, a second oxide layer, a second monocrystalline silicon layer, a third oxide layer and a mask layer on a substrate; etching the mask layer, the third oxide layer, the second monocrystalline silicon layer and the second oxide layer to form a first opening and a second opening; carrying out epitaxial growth in the first opening and the second opening to ensure that the inner surfaces of the first and second openings are consistent with the surface of the second monocrystalline silicon layer; etching the mask layer, the third oxide layer, the second monocrystalline silicon layer, the second oxide layer and the first monocrystalline silicon layer to form a first groove, a second groove and a third groove; depositing plasma oxides in the three grooves to form groove isolation structures; removing the third oxide layer and the mask layer; and forming a body contact device on the second monocrystalline silicon layer. Compared with the prior art, the device and the manufacturingmethod are capable of decreasing the gathering of stray capacitance and positive electrons, restraining the floating body effect and improving the breakdown voltage at the same time.

Description

technical field [0001] The invention relates to the technical field of semiconductors, in particular to a silicon-on-insulator radio frequency switching device and a manufacturing method thereof. Background technique [0002] Silicon is the most widely used primary raw material in the semiconductor industry, and most chips are made of silicon wafers. Silicon-on-insulator (SOI) is a special silicon chip whose main feature is to insert an insulating layer (buried oxide layer) between the active layer and the substrate layer to isolate the electrical connection between the active layer and the substrate. Connection, this structural feature brings many advantages such as small parasitic effect, fast speed, low power consumption, high integration, and strong radiation resistance to silicon-on-insulator devices. [0003] In the existing technology, such as Figure 1 to Figure 3 , figure 1 is a top view of a silicon-on-insulator RF switching device structure in the prior art, ...

AI Technical Summary

Problems solved by technology

In the top view, the monocrystalline silicon is in the shape of a "T", the source and drain electrodes are located on the vertical sides of the "T", and the body region contact device connection area is located above the horizontal of the "T". image 3 It is the state-of-the-art silicon-on-insulator RF switching device structure along the figure 1 The cross-sectional schematic diagram of the line BB', PW is the body region of the transistor, the distance from the entire body region to the body contact node P+ is relatively long, about 10 microns, therefore, there is a parasitic resistance, and when the MOSFET is turned on, it collides at the drain end The holes generated by ionization cannot be exported to PW everywhere in time, causing the potential of the base of the parasitic NPN to rise, the parasitic NPN is turned on, and the MOSFET is more prone to breakdown

Images