HIGH PERFORMANCE THIN FILMS FOR MICROCIRCUITS (CAPACITORS).
Abstract
Thin-film capacitors consisting of hafnium - hafnium dioxide were fabricated and evaluated. The hafnium film is deposited onto a passive substrate by cathodic sputtering. A rate of deposition of 330 A/min permits the deposition of hafnium films with a specific resistivity of about 100 micro ohm-cm. The dielectric hafnium dioxide is produced by wet and plasma anodization. Experiments show that forming of the oxide film by plasma anodization is limited to a forming voltage (V sub f) of about 60 volts as compared to 250 volts for the wet anodization process. Preliminary measurements on the dielectric constant by the 'wedge' technique show a k of 45. The temperature coefficient of capacitance for wet anodized samples has been found to be +125 ppm/degrees C between -196C and 350C. Measurements on the frequency dependence show that the capacitance decreases by only 3 percent at 300 kHz as compared to the 1 kHz values. Preliminary life tests at +125C show that thin-film hafnium - hafnium dioxide capacitors prepared by wet anodization exhibit a high stability as compared to plasmionically-anodized hafnium -oxide thin-film capacitors. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 31, 1966
- Accession Number
- AD0632141
Entities
People
- Franz Huber
- W. Witt