Manufacture method of depletion mode metal-oxide-semiconductor field effect transistor (MOSFET)

Abstract

The invention discloses a manufacture method of a depletion mode metal-oxide-semiconductor field effect transistor (MOSFET). The manufacture method includes providing a first mingling type mingled substrate, forming a first mingling type epitaxial layer on one face of the substrate, forming a first mask layer on the epitaxial layer, conducting first ion injection with the first mask layer as a mask, forming a second mingling type trap in the epitaxial layer, removing the first mask layer, conducting first annealing, forming a second mask layer on the epitaxial layer and the trap, conducting second ion injection with the second mask layer as a mask and forming a first mingling type ion injection channel in the middle of the trap. The channel of the depletion mode MOSFET is formed by adopting ion injection of the mask layer, and high performance can be ensured by means of accurate structure, position and depth of the channel.

Description

technical field [0001] The invention belongs to the technical field of semiconductor manufacturing, in particular to a method for manufacturing a depletion MOSFET. Background technique [0002] MOSFETs are divided into enhancement-mode MOSFETs and depletion-mode MOSFETs. For the depletion-mode MOSFET, because a large number of ions are doped in the oxide layer of the source and drain electrodes, even when the gate voltage VGS=0, under the action of the doped ions in the oxide layer, the surface layer of the substrate will induce The bottom doping type is opposite and the majority carriers form an inversion layer, that is, there is a channel between the source and the drain. As long as a forward voltage is applied between the source and the drain, the drain current can be generated; when the gate voltage VGS is applied, Most carriers will flow out of the channel, the inversion layer becomes narrower and the channel resistance increases. When the gate voltage VGS increases to...

AI Technical Summary

Problems solved by technology

The traditional depletion-mode MOSFET manufacturing method is not accurate enough to control the position and depth of the channel, and the ion implantation of the oxide layer will also cause disadvantages to other regions (such as the source region and the drain region). effect, making it impossible to manufacture high-quality depletion-mode MOSFETs

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