公开(公告)号：BR8605249A

公开(公告)日：1987-07-28

申请号：BR8605249

申请日：1986-10-28

Applicant: IBM

Inventor： COOK ROBERTO KIMBALL ,  SHEPARD JOSEPH FRANCIS

IPC: H01L21/302 ,  H01L21/033 ,  H01L21/3065 ,  H01L21/72

Abstract: A method is disclosed for making submicron openings in a substrate. A mesa is formed on the substrate by reactive ion etching techniques. A film is deposited over the entire structure and the mesa is selectively etched away to yield a submicron-sized opening in the film. Using the film as a mask, the substrate exposed thereby is reactively ion etched. An example is given for producing an emitter mask for a polycrystalline silicon base bipolar transistor.