Accession Number : ADD006050

Title :   Laser Annealing Technique for Improving the Detectivity of Detector Elements in Photovoltaic Detector Arrays.

Descriptive Note : Patent Application,


Personal Author(s) : Bartoli,Flibert J ; Esterowtiz,Leon ; Allen,Roger E

Report Date : 03 May 1979

Pagination or Media Count : 13

Abstract : This patent application covers a method of improving the detectivity and other performance characteristics of individual detectors of a fully processed, high-density, photovoltaic detector array. Each detector of a detector array is tested to determine its performance characteristics. If there are some detectors of the array that do not meet the standards required, the nonstandard detectors are annealed at the spot of the defect by use of a laser to correct the situation. The laser pulse is shaped as necessary and is of an intensity that an adjacent detector or other near-by areas are not affected by the laser output. Pulse durations between 10 to the minus 9th power and 1,000,000 sec are acceptable to avoid the spreading of heat. Laser wavelengths much shorter than the cutoff wavelength of the material will concentrate the heating in the region near the surface. The irradiation procedure and sequence must be designed for different photovoltaic detector types and array designs. Once the optimized laser wavelength, power density, pulse durations, and irradiation pattern have been determined for different types of arrays and the different corrective annealing steps (that is, contacts, junction edge, interelement region, etc.) have been determined for specific types of arrays, a large number of arrays of the same type may be treated employing the same optimized parameters. This procedure may also be used for single element detectors as well as for arrays. (Author)

Descriptors :   *Patent applications, *Optical detectors, Photovoltaic effect, Electrooptics, High frequency, Pulsed lasers, Semiconductors

Subject Categories : Information Science
      Optical Detection and Detectors

Distribution Statement : APPROVED FOR PUBLIC RELEASE