Method for detecting particle pollutant on surface of electrostatic suction disc

Abstract

The invention discloses a method for detecting a particle pollutant on a surface of an electrostatic suction disc. A positive / negative switching voltage is applied to the electrostatic suction disc before an existing particle detection process, an inert gas is continuously introduced to an etching cavity, helium is introduced into an air passage in a surface of the electrostatic suction disc, andthe surface of the electrostatic suction disc is brushed. With the adoption of the method disclosed by the technical scheme, the particle pollutant on the surface of the electrostatic suction disc canfall off, the stability of the etching cavity is judged according to particle number and size detected on a control wafer, the subsequent wafer etching defect caused by the particle pollutant of theetching cavity is prevented, and the yield of the wafer is improved.

Description

technical field [0001] The invention relates to a semiconductor etching process, in particular to a method for detecting particle pollutants on the surface of an electrostatic chuck. Background technique [0002] In an ideal plasma etching process, the etching gas completely participates in the reaction to form a gaseous product, which is pumped out of the reaction chamber by a vacuum pump after the reaction. However, in the actual etching process, some of the generated solid products adhere to the etching chamber and the electrostatic chuck, and cannot be removed by the vacuum pump, causing pollution to the etching reaction chamber. As the subsequent etching proceeds, the solid products continue to accumulate, forming particulate contamination of components. At the same time, as the size of the etched products becomes smaller and the stacking structure becomes more and more complex, the reactants and products during the etching process are also corresponding. Tiny particul...

AI Technical Summary

Problems solved by technology

However, in the etching process, the particles on the surface of the electrostatic chuck will be excited during the etching process. Since there is no wafer barrier on the surface of the chuck, the particles will be transferred to the focus area on the edge of the electrostatic chuck by the airflow during the excited state. During the etching process, it is sputtered to the wafer surface again to form etching defects

Therefore, the above existing detection methods are difficult to detect the state of particles on the surface of the electrostatic chuck

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