Through-hole electrode substrate, mems device, manufacturing method of mems device, and multilayered device

The manufacturing method according to 12, wherein

• the substrate is a silicon substrate,
• the through-hole electrode formation step includes:
• a step of forming at least one trench from the first surface of the substrate toward an inside of the substrate;
• a step of diffusing an impurity from a wall surface and a bottom surface of the at least one trench into the substrate to form an impurity diffusion region that later serves as at least one electrode;
• a step of forming the insulating film in the at least one trench;
• and
• a polishing step of polishing a surface of the substrate opposite to the first surface so that the impurity diffusion region serves the at least one electrode, and
• the polishing step is performed after the circuit formation step, and is performed until the insulating film and the impurity diffusion region are exposed.

The manufacturing method according to 12, wherein

• the through-hole electrode formation step includes:
• a step of forming at least one trench from the first surface of the substrate toward an inside of the substrate;
• a step of forming the insulating film in the at least one trench;
• a polishing step of polishing a surface of the substrate opposite to the first surface to expose the insulating film;
• a step of forming at least one through hole by removing a part surrounded by the insulating film from the substrate after the polishing step;
• and
• a step of forming the at least one electrode in the at least one through hole, and
• the polishing step is performed after the circuit formation step.