| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a semiconductor device manufacturing method which has high degree of freedom in processes and which enables other processing other than forming an element isolation layer of a trench structure even in the middle of forming the element isolation layer.SOLUTION: A semiconductor device manufacturing method comprises: depositing a CVD oxide film 13 above a silicon substrate 1 to cover a polysilicon film 7 remaining in a trench 3; subsequently depositing a BPSG film 15 on the CVD oxide film 13; planarizing a surface of the BPSG film 15; subsequently performing a wet etching treatment on the BPSG film 15 and the CVD oxide film 13 to remove all of the BPSG film 15 and leave the CVD oxide film 13 at least in the trench 3; and subsequently performing a dry etching treatment on the CVD oxide film 13 remaining in the trench 3. In the process of depositing the BPSG film 15, a B concentration and a P concentration of the BPSG film 15 are preliminarily adjusted such that an etching rate of the BPSG film 15 in the wet etching treatment becomes not greater than an etching rate of the CVD oxide film 13.</p> |
