Research and Development of Low-Light-Level/Near IR Camera Tube with Solid-State Array Target.
Abstract
The primary effort during this reporting period was devoted to: (1) preparation and evaluation of alloy-type Ge homojunction diode arrays and, (2) assembly and testing of a prototype cooled camera tube. In addition, work was started on: (1) alternate methods of junction formation in Ge by thermal diffusion of acceptors, and (2) epitaxial growth of GaAs layers on Ge as a means of stabilizing the scene side of the target with regard to improved short wavelength response. Eight Ge homojunction diode targets were prepared by alloy techniques and modified mesa etching processes. Individual diodes were evaluated in a pumped test cryostat which stimulates conditions of actual target operation. A feature of the apparatus is that target sections can be mounted to headers and diodes contacted by lead bonding. Dark current, relative spectra response, and junction capacitance were measured as a function of bias voltage at room temperature and 77K in vacuum of approximately 10 to the minus 8th power torr. Process changes have resulted in lower values of dark current. A camera tube with a cryogenic liquid cooling ring was assembled and successfully cycled from 300K to 77K, without losing vacuum; target temperature measured within 4K of liquid N2. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 1970
- Accession Number
- AD0870994
Entities
People
- Michael Poleshuk