Substrate processing method and substrate processing apparatus

Abstract

A substrate processing method which is capable of easily removing residue caused by hydrofluoric acid. By the substrate processing method, a substrate is processed which has a thermal oxide film formed by a thermal oxidation process and a BPSG film containing impurities. In an HF gas feeding step, an HF gas is fed toward the substrate, and in a cleaning gas feeding step, a cleaning gas containingat least NH3 gas is fed toward the substrate fed with the HF gas.

Description

technical field [0001] The present invention relates to a substrate processing method and a substrate processing device, in particular to a substrate processing method for processing a substrate formed with a thermal oxide film and an oxide film containing impurities. Background technique [0002] Wafers (substrates) for semiconductor devices are known to have a thermal oxide film formed by thermal oxidation treatment and an oxide film containing impurities such as BPSG (BoronPhosphorous Silicate Glass) film formed by CVD treatment or the like. The BPSG film is formed on the polysilicon film to partially expose the polysilicon film, and functions as a hard mask when the polysilicon film is etched. In addition, a thermal oxide film constitutes a gate oxide film. [0003] Furthermore, after etching the polysilicon film on this substrate, it is required not to remove (etch) the thermal oxide film but to selectively remove (etch) the BPSG film. [0004] When etching an oxide f...

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Problems solved by technology

This residue can cause problems such as short circuits in semiconductor devices manufactured from the wafer

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