A method for forming body contact of soi MOSFET using sacrificial layer

Abstract

The invention provides a body contact forming method by utilizing an SOI (silicon on insulator) MOSFET (metal oxide semiconductor field effect transistor) of a sacrificial layer. The method comprises the following steps of: depositing a buried SiO2 layer (2) on a semiconductor substrate (1) on a bottom layer, and depositing a SiGe mask membrane (3) on the buried SiO2 layer (2); etching for the first time and exposing the buried SiO2 layer (2); etching for the second time and maintaining the buried layer SiO2 layer (2) with a large area at the right side of the SiGe mask membrane (3); carrying out epitaxial growth of a silicon membrane (5) at the top layer; forming a gate oxide layer (7), and depositing a polycrystalline gate (8); etching for the third time and removing the silicon membrane (5) at the top layer of a glue-free part; etching horizontally for the fourth time and removing the remained SiGe mask membrane (3a); and carrying out epitaxial growth and compensating the silicon membrane at the top layer (5), pouring P+ ions, and depositing a metal electrode. The body contact forming method by utilizing the SOI MOSFET of the sacrificial layer has the advantages of reducing the use of the mask membrane plate, simplifying the manufacturing technology flow, and lowering the manufacturing cost.

Description

technical field [0001] The invention relates to a method for forming electronic components. Specifically, it is a method for forming SOI MOSFET body contact using a sacrificial layer. Background technique [0002] As a full dielectric isolation technology, SOI technology has many incomparable advantages over bulk silicon technology. However, SOI devices also have some parasitic effects, among which the floating body effect of partially depleted SOI devices is the biggest problem compared with bulk silicon devices, which has also become one of the reasons restricting the development and wide application of SOI technology. Floating body effect will produce kink effect, drain breakdown voltage reduction, abnormal subthreshold slope, etc., which seriously affect the performance of the device. [0003] Due to the impact of the floating body effect on device performance, how to suppress the floating body effect has become a hot spot in the research of SOI devices. The suppressi...

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Problems solved by technology

Although this method can suppress the floating body effect of SOI MOSFET devices, it sometimes destroys the isolation effect of SOI MOSFET devices. The manufacturing process of the device is complicated, and the manufacturing steps are cumbersome, which is not conducive to reducing the production cost

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