Patent · US Expired

Sputtering targets with low mobile ion contamination

US4331476A · kind A · utility

11Cited by
8References
7Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 31, 1980
Grant dateMay 25, 1982
Priority date
Expiry dateJan 31, 2000

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB22F2201/20
  • WIPO fieldMaterials, metallurgy
  • WIPO sectorChemistry

Abstract

Metallic sputtering targets having minimal mobile ion contamination are produced by forming a compacted slab of particles of the constituent metal(s) in an isostatic pressing operation. The slab is then transferred to a heat resistant support faced with a material, such as alumina, that is inert at high temperatures. Next, the supported slab is placed in a vacuum oven and heated to a temperature sufficient to bond the metal particles together and volatilize mobile ion contaminants. The sintered slab is usable as a cathodic sputtering target with minimal additional treatment. The level of mobile ion contaminants in the completed target may be monitored by fabricating an MOS capacitor using the target, plotting its capacitance versus applied voltage over a suitable range, then measuring the extent to which the plot shifts after a high temperature-positive bias stress treatment.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.