Voltage contrast method for determining abnormal short-circuit position

Abstract

The invention discloses a voltage contrast method for determining an abnormal short-circuit position. The method comprises the following steps: selecting a sample and grinding the sample to a suspicious level; carrying out scanning on a suspicious region by multiple times, storing voltage contrast pictures correspondingly, and observing whether a single region with the abnormal voltage contrast exists and whether two or more regions changing with the single region exist in a target region; for the one or multiple observed regions with abnormity, magnifying the abnormal degree of the voltage contrast image by using a short-circuit grounding method so as to find out a suspicious short-circuit point; and after short-circuit point determination, carrying out sample preparation based on focus ion beam fracture surface observation and transmission electron microscope sample preparation and observing short-circuit elements. According to the method, the abnormal short-circuit position existing in an integrated circuit and short-circuit factors can be determined rapidly and accurately; and the efficiency of an integrated circuit failure analysis can be improved.

Description

technical field [0001] The invention relates to the field of integrated circuit design, in particular to a voltage contrast method for judging the position of an abnormal short circuit in integrated circuit failure analysis. Background technique [0002] During the manufacturing process of integrated circuits, due to process defects, equipment errors or even human factors, short circuits may be caused inside the chip. This short circuit can occur between polysilicon and polysilicon, polysilicon and metal, metal and metal, metal and active region, active region and active region, and active region and polysilicon. However, this abnormal short circuit can cause serious problems such as increased power consumption of the chip, abnormal function, and data loss. It is very important to be able to detect defects that occur during the manufacturing process of integrated circuits in a timely manner to improve the yield rate. Due to the continuous shrinking of the feature size of th...

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Problems solved by technology

Due to the uncertain position of the defect and the lack of purpose, this method requires a lot of manpower and equipment time resources, but the effect is not good.

Moreover, due to the resolution problem, it is likely that the weak short is forgotten or ignored during the cutting process

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