Method for acquiring reference product yield of new product on production line

Abstract

The invention provides a method for acquiring the reference product yield of a new product on a production line. The method comprises the following steps of: introducing yield screening, overkill rate compensation and a defect density correction coefficient; substituting in a defect density formula to obtain a defect density correction formula; and calculating to acquire the intrinsic defect density of the production line so as to accurately acquire the reference product yield of the new product on the production line.

Description

technical field [0001] The invention relates to the field of semiconductors, in particular to a method for obtaining the yield rate of a benchmark product of a new product in a production line. Background technique [0002] At present, the semiconductor manufacturing process is to grow hundreds of thousands of identical chips on a wafer at the same time, and the wafer after all the processes are completed is also called a bare chip. Qualified chips are selected by testing the bare chips, and cut and packaged into products. Usually, the method for calculating the product yield Yield of a certain product produced by a wafer production line is to first randomly select a number of dies of this product produced by the same wafer production line (the number can vary according to the production situation), and then test and select All the chips on all the dies, using Yield's calculation formula: [0003] Yield = number of qualified chips / total number of chips (0.1) [0004] Ge...

AI Technical Summary

Problems solved by technology

Although the formula (0.2) has already included the consideration of the chip size factor of different products, there are two problems in the practical application of this formula: (1) the chip with a small chip size has a large defect density, (2) the memory Chips with a large proportion of the area to the chip area have a high defect density

[0012] The reason why the defect density of products with a large proportion of the storage area to the chip area is that the circuit design of the storage area is usually the area with the densest device density on the chip, and some relatively small particles have little effect on other areas of the chip or even can Neglect; but for the storage area, due to the tight circuit layout, very small particles are likely to affect the product yield, which eventually leads to low product yield and high defect density for products with a large proportion of the storage area to the chip area

[0013] It can be seen from the above that the formula (0.2) cannot obtain the inherent defect density of the wafer production line, so it cannot accurately predict the yield rate of the benchmark product of the new product

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