Method used for reducing wafer edge yield test problems

Abstract

The present invention provides a method used for reducing wafer edge yield test problem. The method comprises a first step of obtaining a patterned photomask and the patterned photoresist adopted to execute the photoetching on a passivation layer of a wafer; a second step of inverting the patterned photomask to obtain an inverted patterned photomask, and changing the positive and negative attributes of the patterned photoresist on the condition of keeping a constant photoresist pattern to obtain the reverse patterned photoresist; a third step of utilizing the inverted patterned photomask and the reverse patterned photoresist to execute the photoetching on the wafer. According to the method used for reducing the wafer edge yield test problems of the present invention, the photomask and the photoresist of the passivation layer both become inverted, so that the figures of other parts, except a predetermined part starting at an edge position, in the wafer, do not change, and the passivation layer is retained from the edge to the predetermined part, and accordingly, a test false failure problem is not generated.

Description

technical field [0001] The present invention relates to the fields of semiconductor manufacturing and semiconductor testing, and more particularly, the present invention relates to a method for reducing wafer edge yield testing problems. Background technique [0002] Wafer-level testing (CP Test, also known as wafer-level testing) is an important step in the semiconductor manufacturing process. Early device characterization can be obtained using wafer-level testing. [0003] However, some products will encounter the problem of low yield at the edge of the wafer when performing wafer yield testing, and even some products with a large single-chip area have a yield rate as low as 5%. This is not expected. [0004] In fact, this low wafer edge yield is related to test pin sticks. Specifically, an incomplete chip (partial die) at the edge of the wafer can cause other complete chips to be directly judged to be invalid due to leakage of electricity from the pins of the incomplet...

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Problems solved by technology

As a result, this low yield at the wafer edge associated with test pin sticks as described above

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