Method for determining groove etch time and method for preparing isolation of shallow channel

Abstract

The invention relates to a method for determining the etching time of a plow groove, which comprises the steps as follows: a first mask which has a plow groove design is provided and the light transmission ratio of the first mask is obtained; the value of the light transmission ratio is input into the functional relationship of the light transmission ratio of a second mask which is obtained beforehand, and the etching time of the plow groove to calculate the etching time of the plow groove which is corresponding to the plow groove design of the first mask, wherein, the second mask is provided with the plow groove design and the plow groove design of the second mask and the plow groove design of the first mask have the same technology nodes. The invention also provides a manufacturing method for the isolation of a shallow plow groove. The technique for obtaining the etching time of the plow groove of the invention is relatively simple and can save time.

Description

technical field [0001] The invention relates to the technical field of semiconductor manufacturing, in particular to a method for determining trench etching time and a manufacturing method for shallow trench isolation. Background technique [0002] In the manufacturing process of semiconductor integrated circuits, shallow trench isolation is formed by forming a trench on a semiconductor substrate and then filling the trench with a dielectric material. The Chinese patent application document with publication number CN1649122A (published on August 3, 2005) discloses a manufacturing method for shallow trench isolation. [0003] Figure 1 to Figure 5 A schematic cross-sectional view of a structure corresponding to each step of the shallow trench isolation manufacturing method disclosed in the Chinese patent application document. [0004] Such as figure 1 As shown, a semiconductor substrate 12 is provided, a pad oxide layer 12A is formed on the semiconductor substrate 12, and ...

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Problems solved by technology

[0009] In the manufacturing method of the shallow trench isolation, the semiconductor substrate 12 at the bottom of the opening 16C is etched, and the semiconductor substrate 12 is formed in the semiconductor substrate 12 such as image 3 The method of the trench 18 shown is generally plasma dry etching. Since there is no etch stop layer during the etching process, the depth of the trench 18 needs to be controlled by the etching time; In the case of a certain etching material, the etching time of the groove is also affected by the density of the groove. For the same depth of the groove, the etching time is different due to the different density; therefore, in order to obtain a depth satisfying The etching time of the groove required requires a large number of experiments, making it difficult to determine the etching time of the groove; especially in the development of new products, in order to obtain the shallow trench isolation in the manufacturing process of the new product The etching time of the trench has to be carried out a large number of experiments, which complicates the process of developing this new product

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