Patent ID: 6825119
Filing Date: 2004-11-30
Classification: G01N,H01L

Abstract:
A method of piping defect detection comprising following steps:providing a sample, the sample comprising: a silicon substrate; a plurality of electric devices disposed on the silicon substrate, the plurality of electric devices comprising a gate; a dielectric layer covering the plurality of electric devices and the silicon substrate, the dielectric layer having a plurality of contact holes disposed on each of the electric devices, wherein at least a void is formed between two adjacent gates due to low uniformity of the dielectric layer coverage; and a polysilicon layer covering the dielectric layer and electrically connecting to the electric devices through the contact holes, wherein the polysilicon film fills the contact holes to form a plurality of contact plugs and fills the void to form a piping defect; performing a chemical mechanical polishing (CMP) process to remove the polysilicon layer and over polish the dielectric layer; performing a wet etching process to etch the dielectric layer selectively; and inspecting the sample with a light source to search for the piping defect, wherein the polysilicon layer appears opaque but the dielectric layer appears transparent under the light source.