High-voltage transistor and manufacturing method thereof

Abstract

The invention provides a manufacturing method of a high-voltage transistor, wherein the process step of specially forming a metal-silicide blocking layer at a silicon-substrate active area can be omitted by once forming a first virtual grid electrode, a second virtual grid electrode and a working grid electrode which are mutually separated above a high-voltage well; before ion injection is carried out to form a source and a drain of the high-voltage transistor, a graphical photoresist needs to be formed on a whole silicon substrate; and when gaps among the first virtual grid electrode, the second virtual grid electrode and the working grid electrode are smaller, a sufficiently-thick layer is formed from a lateral wall between the adjacent grid electrodes, and self-aligned ion injection is realized at the area by directly using the adjacent grid electrodes on the high-voltage well and the lateral wall between the adjacent grid electrodes as masks without covering the photoresist between the adjacent grid electrodes at the time, so that the process of manufacturing a mask plate before forming the graphical photoresist is simplified. On the basis of the manufacturing method, the invention also provides the high-voltage transistor.

Description

technical field [0001] The invention relates to the field of transistors, in particular to the field of high-voltage transistors. Background technique [0002] High-voltage devices are an important part of the modern integrated circuit industry. They are widely used in power management, panel display, industrial control, etc., and their operating voltage ranges from tens of volts to hundreds of volts. There are many kinds of high-voltage devices, and the structure of a common P-type high-voltage transistor is as follows Figure 6 As shown, its specific production method is as follows Figure 1 to Figure 5 Shown: [0003] Such as figure 1 As shown, a P-type silicon substrate is provided, and the first ion implantation forms a high-voltage N-type well 11 on the P-type silicon substrate, and is used to form an N-type high-voltage well 11 on the P-type silicon substrate. Shallow trenches isolated from other active areas, forming an oxide layer on a silicon substrate to fill ...

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Problems solved by technology

[0011] It can be seen from the above that the manufacturing method of high-voltage transistors in the prior art is too complicated, and it is indeed necessary to provide a new manufacturing method of high-voltage transistors

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