Method of forming gate oxide layer

Abstract

The invention provides a method of forming a gate oxide layer. The method comprises the steps of S1, conducting the oxidation growth on the upper surface of a semiconductor substrate to form an oxide layer; S2, etching to remove the oxide layer located at a first position to expose the part of the semiconductor substrate that is corresponding to the first position; S3, conducting the oxidation growth on the exposed semiconductor substrate to form a first gate oxide layer of H1 in thickness; S4, etching to remove the first gate oxide layer at a second position to expose the part of the semiconductor substrate that is corresponding to the second position; S5, conducting the oxidation growth on the exposed semiconductor substrate to form a second gate oxide layer of H2 in thickness, wherein H2<H1; and S6, implanting ions into the semiconductor substrate below the first gate oxide layer and the second gate oxide layer. Through adjusting the manufacturing process of the first gate oxide layer and the second gate oxide layer, the process of implanting ions and adjusting the threshold voltage respectively is replaced. Therefore, the problems that the process is complicated and the cost is high can be solved.

Description

technical field [0001] The present application relates to the technical field of semiconductor manufacturing, and in particular, to a method for forming a gate oxide layer. Background technique [0002] The dual core GOX process is a conventional process currently used in the 45nmLP (low power process) and 28nm PloySION (polysilicon gate + silicon oxynitride insulating layer) process for speed-up. This process requires the formation of two thickness difference around the gate oxide. For example, a gate oxide layer with a normal thickness is used for conventional logic cells that can withstand the leakage current of the entire chip, and a gate oxide layer with a thinner thickness is used for speed push areas that control chip speed. [0003] At present, in order to obtain sufficient saturation current in the boosting region, after forming gate oxide layers with different thicknesses, ion implantation is used to adjust the threshold voltage of the boosting region, so as to ...

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Problems solved by technology

[0014] The purpose of this application is to provide a method for forming a gate oxide layer to solve the problems of cumbersome steps and high cost in the prior art

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