公开(公告)号：FR2410361A1

公开(公告)日：1979-06-22

申请号：FR7828299

申请日：1978-09-26

Applicant: IBM

Inventor： CUOMO JEROME J ,  GAMBINO RICHARD J ,  HARPER JAMES M

IPC: C23F4/00 ,  H01J37/34 ,  H01L21/302 ,  H01L21/3065 ,  H01J37/30 ,  H01J37/20

Abstract: Bombardment some intermetallic compounds above a sufficient target voltage Vo can be used for etching substrates. Etching a substrate located in an evacuated chamber involves bombardment of an intermetallic compound or alloy comprising for example Au, Pt, etc. and a metallic element such as Eu, La, Cs, etc. with ions so that a large flux of negative Au, Pt, etc. ions is produced which etches a substrate located nearby. Such bombardment is achieved by placing an Au, Pt, etc. intermetallic composition target in a sputtering chamber using an argon sputtering gas, located opposite from a substrate. A gold alloy or compound target can be SmAu, EuAu, LaAu, CsAu, etc. The target of Au, Pt, etc. and a rare earth element, etc. is bombarded by sputtering gas atoms excited by RF or D.C. energy, creating negative metal ions by sputtering. Instead of depositing upon the substrate, the negative ions cause a cascade of energetic sputtering gas atoms and metal atoms to etch the substrate surface directly beneath the target as outlined by ground shields. Outside that region negative ion and rare earth metals deposit on the substrate. Bombardment with an ion gun, neutral atoms or energetic particle sources or an ionic molecular source may produce negative ions. A use is ion milling. A target material is useful as a negative ion source of metal B in an intermetallic compound of metals A and B if A has ionization potential IA and B has electron affinity EAB such that IA-EAB > about 3.4 electron volts or if there is a electronegativity difference DELTA X greater than about 2.55.