Field element of high-voltage semiconductor element

Abstract

The invention discloses a field element of a high-voltage semiconductor element. The field element comprises a first conducting type substrate, a first trap in a second conducting type, a second trap in a first conducting type, a first doping zone in a first conducting type, a leading wire and a conductive body. The first trap is formed in the substrate and extends downwards from the surface of the substrate. The second trap is formed in the substrate and extends downwards from the surface of the substrate. The second trap is connected to one side of the first trap in an adjacent mode. The substrate is placed on the other side of the first trap. The first doping zone is formed at the second trap, and a certain distance is formed between the first doping zone and the first trap. The doping concentration of the first doping zone is larger than that of the second trap. The leading wire is electrically connected with the first doping zone and stretches across the upper position of the first trap. The conductive body is placed between the leading wire and the first trap. The conductive body is placed below the leading wire and correspondingly stretches across the first trap. The conductive body and the leading wire are electrically isolated. When the high-voltage semiconductor element is operated, a high voltage is exerted on the leading wire, a fixed bias voltage is exerted on the conductive body, or no external voltages are exerted on the conductive body, and the field element can be effectively prevented from being started.

Description

technical field [0001] The present invention relates to a field element capable of effectively improving the threshold voltage (Threshold voltage) of a parasitic field element of a high-voltage semiconductor element. Background technique [0002] In recent decades, the semiconductor industry has continued to shrink the size of semiconductor structures while simultaneously improving speed, performance, density, and unit cost of integrated circuits. For high-voltage or ultra-high-voltage semiconductor components (such as metal oxide semiconductor MOS), when the metal line is connected to the component in the silicon process, the problem of turning on the parasitic field element will be induced in some areas where the metal line crosses. . That is to say, the maximum operating voltage of the MOS transistor may be lower than its breakdown voltage under the influence and limitation of the threshold voltage (Vth) of the turned-on parasitic field element under the high voltage ope...

AI Technical Summary

Problems solved by technology

That is to say, under the high-voltage operation of the MOS transistor, the maximum operating voltage of the MOS transistor may be lower than its breakdown voltage due to the influence and limitation of the threshold voltage (Vth) of the parasitic field element being turned on.

[0003] The currently proposed method to avoid turning on the field element: for example, forming a pad in the high-voltage N-type well of the field element so that there is no voltage difference between the drain terminal and the field element, and no current flows, but the area of ​​the pad is large and takes up space. , and it is easy to cause the risk of high-voltage N-type well insulation isolation failure

In addition, there is also a method of increasing the oxide thickness above the high-voltage N-type well of the field element to make it more difficult for the high-voltage N-type well to reverse (channel reverse) under high-voltage operation, thereby increasing the difficulty of turning on the field element. However, this method increases the The time of the thermal process (formation of oxide), not only requires an extra thermal budget (extra thermal budget), but its heat accumulation may also have adverse effects on other components

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