| 摘要 |
PROBLEM TO BE SOLVED: To provide a manufacturing method of a silicon device capable of making it easy to hold a pressure in a cavity portion constant.SOLUTION: A manufacturing method of a pressure sensor 1 includes: a first recess portion forming step of preparing a substrate 50 having a first recess portion 53 and a piezoresistive element 20 disposed on a bottom portion of the first recess portion 53; an AlOfilm forming step of forming an AlOfilm 54 on at least a part of an inner surface of the first recess portion 53 of the substrate 50; a sacrifice layer forming step of forming a sacrifice layer 55 on the first recess portion 53; a lid layer forming step of forming a lid layer 56 having a through-hole 57 overlapping with the first recess portion 53 in a plain view and covering an opening of the first recess portion 53; a sacrifice layer etching step of performing etching from the through-hole 57 to the sacrifice layer 55 by using hydrofluoric acid vapor; and a through-hole sealing step of sealing the through-hole 57.SELECTED DRAWING: Figure 3 |
