R.f.sputter plating method and apparatus employing control of ion and electron bombardment of the plating

Abstract

Abstract AN R.F. SPUTTER PLATING METHOD AND APPARATUS IS DISCLOSED. THE PLATING APPARATUS INCLUDES A PARTIALLY EVACUATED DEPOSITION CHAMBER CONTAINING A PAIR OF ELECTRODES EXCITED WITH RADIO FREQUENCY ENERGY TO PRODUCE A RADIO FREQUENCY PLASMA DISCHARGE IN THE REGION THEREBETWEEN. THE R.F. DISCHARGE DEFINING ELECTRODES ARE OPERATED AT A FLOATING POTENTIAL SUCH THAT, BY THE NATURE OF THE PLASMA DISCHARGE, RELATIVELY HIGH NEGATIVE SELF-BIAS POTENTIAL IS ESTABLISHED ON THE R.F. ELECTRODES. A TARGET MATERIAL IS PLACED ON THE R.F. ELECTRODES TO BE SPUTTERED BY ION BOMBARDMENT, SUCH IONS EMANATING FROM THE PLASMA DISCHARGE. A COLLECTOR ELECTRODE IS DISPOSED TO RECEIVE THE SPUTTERED TARGET MATERIAL TO PLATE THE COLLECTOR ELECTRODE OR ITEMS CARRIED THEREON. A PAIR OF TRANSPARENT GRID STRUCTURES ARE DISPOSED INTERMEDIATE THE COLLECTOR ELECTRODE AND THE PLASMA DISCHARGE REGION. A FIRST ONE OF THE GRID STRUCTURES, ADJACENT THE PLASMA DISCHARGE, IS OPERATED AT GROUND POTENTIAL TO PREVENT PERTURBATION OF THE DISCHARGE, WHEREAS THE SECOND GRID STRUCTURE DISPOSED INTERMEDIATE THE FIRST GRID STRUCTURE AND THE COLLECTOR STRUCTURE IS OPERATED AT A POTENTIAL POSITIVE WITH RESPECT TO THE DISCHARGE FOR REPELLING POSITIVE IONS. THE COLLECTOR STRUCTURE IS OPERATED AT A POTENTIAL NEGATIVE WITH RESPECT TO THE SELF-BIAS POTENTIAL ON THE TARGET ELECTRODES TO REPEL ELECTRONS EMANATING FROM THE DISCHARGE REGION, WHEREBY ION AND ELECTRON BOMBARDMENT OF THE ITEMS BEING PLATED IS CONTROLLED.

Inventors

• 👤 Lawrence T Lamont Jr

Bibliographic Details