Patent · US Expired

Ultrasonic cleaning apparatus

US4501285A · kind A · utility

16Cited by
5References
7Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 5, 1982
Grant dateFeb 26, 1985
Priority date
Expiry dateApr 5, 2002

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S134/902
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

Ultrasonic transducer apparatus for cleaning applications and method for cleaning wafers of semiconductor material in which the method includes positioning the wafer proximate to but closely spaced away from a cleansing face of the ultrasonic transducer, supplying space between the cleansing face and the wafer with a cleansing fluid through an orifice in the cleansing surface and ultrasonically vibrating the cleansing face transversely to the wafer by applying an electrical signal to piezoelectric material symmetrically disposed about the orifice in the cleansing face via which the cleansing fluid is supplied, with the ultrasonic transducer including piezoelectric material symmetrically disposed with respect to the orifice in the cleansing face through which the cleansing fluid is supplied. The piezoelectric material is preferably in the form of a plurality of discreet piezoelectric elements which are provided with an input signal via a common input terminal where all of the plurality of piezoelectric elements are mechanically coupled to the cleansing face so that the piezoelectric elements, the mechanical coupling structure and a cleansing face ultrasonically vibrate as a single i…

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