Semiconductor detecting system and measuring method of etchback depth

Abstract

The invention discloses a semiconductor detecting system and a measuring method of the etchback depth. The measuring method comprises the following steps of: arranging a standard template, then carrying out image acquisition on an object to be detected, acquiring images under real condition, carrying out comparison with the standard template, and thus judging the depth condition after etchback. The method disclosed by the invention is simple and easy and is beneficial for finding defects at an early stage, so that the cost can be greatly saved, and the yield of produced devices can be better controlled.

Description

technical field [0001] The invention relates to the field of integrated circuit manufacturing, in particular to a semiconductor detection system and a method for measuring the depth of engraving back. Background technique [0002] Nowadays, Power MOS Devices have been widely used in many electronic fields. This type of device needs to be able to withstand large voltage, current and power loads. Under the practical requirements, trench MOS devices (Trench MOS) have become a relatively mature type that can better meet the needs. [0003] The recess (poly recess) formed by etching back (etchback) of polysilicon in the trench MOS manufactured by the existing process must have a certain range limit, over-etching or insufficient etching will be due to the height of the polysilicon (that is, the depth of the recess) cannot meet the needs And affect the performance of the device, specifically, when over-etching, that is, the depth of the groove is too deep, it will make the channel...

AI Technical Summary

Problems solved by technology

[0003] The recess (poly recess) formed by etching back (etchback) of polysilicon in the trench MOS manufactured by the existing process must have a certain range limit, over-etching or insufficient etching will be due to the height of the polysilicon (that is, the depth of the recess) cannot meet the needs And affect the performance of the device, specifically, when over-etching, that is, the depth of the groove is too deep, it will make the channel (channel) conduction, and then make the device unable to work; when the etching is not enough, that is, the depth of the groove is shallow or not The formation of grooves will affect the threshold voltage Vt of the device, thereby affecting the performance of the device

[0004] In the existing related processes, except for the use of atomic force microscope (Atomic Force Microscope, AFM), there is no simple and easy method to directly measure the depth of the depression after the polysilicon is etched back, or to have a rough understanding of the depth

However, when there is no need to obtain detailed data on the depth of the depression, the use of AFM is overkill and wastes cost.

[0005] In other words, in the existing process, it is possible to face the embarrassing situation of not only needing to know the situation of the sag in the production process, but also unwilling to use AFM for detailed measurement

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