The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 08, 1983
Filed:
Jun. 23, 1980
Frederick J Leonberger, Lexington, MA (US);
Frederick J O'Donnell, Billerica, MA (US);
Massachusetts Institute of Technology, Cambridge, MA (US);
Abstract
An optoelectronic switch has been formed from a semi-insulating substrate of indium phosphide doped with a deep level impurity and disposed intermediate a microstrip transmission line. One conductor of the transmission line has a small gap in its metallization. Upon illumination of the gap by laser pulses which are absorbed near the semiconductor surface, a photogenerated electron-hole plasma forms thereby providing a conducting path across the gap turning the switch 'on.' A process of fabricating the switch is described, an important feature of which is a heat-treatment process which improves the response time of the switch to .about.50 picoseconds. Another important part of the invention is the formation of an optically semi-transparent metallic film at the gap surface. This provides greater efficiency in the coupling of light into the device at the gap while at the same time maintaining a short electronically non-conductive gap and thus a relatively low ON-state impedance for the switch.