Etching method, method for manufacturing dram capacitor, and plasma processing apparatus

A method for manufacturing a dynamic random access memory capacitor, the method comprising:

• (a) providing a substrate on a substrate support in a chamber, the substrate including a film stack including:
• two or more different silicon-containing films,
• a single-layer film on the two or more different silicon-containing films, the single-layer film including silicon and nitrogen, and
• a mask on the single-layer film, the mask having a side wall defining an opening;
• (b) setting a temperature of the substrate support or the substrate to 10° C. or higher;
• (c) etching the single-layer film using a plasma formed from a first processing gas, the first processing gas including a hydrogen fluoride gas;
• and
• (d) etching the film stack using a plasma formed from a second processing gas.

A plasma processing apparatus, comprising:

• a chamber;
• a substrate support disposed in the chamber;
• a plasma generator;
• and
• processing circuitry configured to:
• (a) control providing a substrate on the substrate support in the chamber, the substrate including a film stack including:
• two or more different silicon-containing films,
• a single-layer film on the two or more different silicon-containing films, the single-layer film including silicon and nitrogen, and
• a mask on the single-layer film, the mask having a side wall defining at least one opening;
• (b) control setting a temperature of the substrate support or the substrate to 10° C. or higher, and
• (c) control etching the single-layer film using a plasma formed by the plasma generator from a first processing gas, the first processing gas including a hydrogen fluoride gas.