Trench manufacturing method and semiconductor isolation structure manufacturing method

Abstract

The invention provides a trench manufacturing method and a semiconductor isolation structure manufacturing method. According to the trench manufacturing method, a hard mask layer and a temporary curing layer are sequentially formed on the surface of a semiconductor substrate; the temporary curing layer generates fluidity when being heated to a certain temperature interval; at least two first depthtrenches are formed with the same depth in the semiconductor substrate; the semiconductor substrate is heated, so that the temporary curing layer can flow into the first depth trench and to be curedinto a trench filler, the depths of the trench filler in the first depth trench being different; and the trench filler and the semiconductor substrate are etched, so that a second depth trench deeperthan the first depth trench is obtained. According to the semiconductor isolation structure manufacturing method, trenches with different depths and widths are respectively formed in the low-voltage region and high-voltage region of a semiconductor substrate by using the trench manufacturing method, so that manufacturing cost is reduced while a process is simplified.

Description

technical field [0001] The invention relates to the field of integrated circuits, in particular to a trench manufacturing method and a semiconductor isolation structure manufacturing method. Background technique [0002] In the manufacture of integrated circuits, for the isolation between individual devices such as different memory cells and different transistors fabricated on the semiconductor substrate, the shallow trench isolation (Shallow Trench Isolation, STI) method is often used, specifically through the A trench with a certain depth is etched on the substrate, and then oxide is filled in the trench to achieve the isolation effect. [0003] With the development of integrated circuit manufacturing technology, devices with different operating voltages will be arranged on the same substrate, such as low-voltage devices and high-voltage devices, and the low-voltage devices and high-voltage devices are respectively arranged in the low-voltage region and high-voltage region...

AI Technical Summary

Problems solved by technology

In order to obtain grooves with different depths, the existing manufacturing process needs to use two photomasks to perform two exposures and combine the etching process to obtain shallower and deeper grooves in the low-pressure area and high-voltage area respectively. The process is complicated and the production cost is high. high

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