Method for removing protruding block defects on polysilicon surface by slow grinding and semiconductor process method

Abstract

The invention provides a method for removing protruding block defects on a polysilicon surface by slow grinding and a semiconductor processing method. The method for removing the protruding block defects on the polysilicon surface by slow grinding comprises the following steps that (1) a semiconductor structure including a polysilicon layer is disposed in a chemical mechanical planarization device, and the protruding block defects are formed on the surface of the polysilicon layer; and (2) chemical mechanical planarization is performed on the polysilicon layer by using a grinding buffer solution containing cerium oxide abrasive particles to remove the protruding block defects on the surface of the polysilicon layer, and the grinding buffer solution is weakly acidic to prevent polysilicon in the polysilicon layer from being oxidized to form silica in the chemical mechanical planarization process. The polysilicon layer is subjected to chemical mechanical planarization by using the acidicgrinding buffer solution containing the cerium oxide abrasive particles, since the removal rate of polysilicon by the cerium oxide abrasive particles is low in an acidic environment, the thickness ofthe removed polysilicon layer can be effectively controlled while removing the protruding block defects on the surface of the polysilicon layer, and thus the loss of the polysilicon layer is reduced.

Description

technical field [0001] The invention relates to the technical field of semiconductor technology, in particular to a method for removing bump defects on the surface of polysilicon by slow grinding and a semiconductor technology method. Background technique [0002] In the existing semiconductor technology, the application of polysilicon is more and more extensive. In the existing polysilicon formation process, after the polysilicon layer is formed, due to the limitations of the polysilicon growth process and the presence of impurities in the polysilicon growth environment, bump defects will be formed on the upper surface of the formed polysilicon layer, and the bump defects The existence of the polysilicon layer will affect the quality of the subsequent process and the performance of the finally formed device structure, and needs to be removed after forming the polysilicon layer. [0003] In order to make the surface of the polysilicon layer have higher flatness after removi...

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Problems solved by technology

[0004] In view of the above-mentioned shortcoming of prior art, the object of the present invention is to provide a kind of slow grinding method that removes bump defect on polysilicon surface, is used to solve the problem of using existing alkaline grinding that contains silicon dioxide abrasive particles in the prior art When the buffer solution removes bump defects on the surface of the polysilicon layer, the removal rate is too fast, and it is easy to remove too much polysilicon layer while removing the bump defects, thereby affecting the performance of the final device structure.

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