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:
Dec. 24, 1996
Filed:
Nov. 13, 1995
Burkhard Altekruger, Alzenau, DE;
Joachim Aufreiter, Alzenau, DE;
Dieter Bruss, Bruchkobel, DE;
Klaus Kalkowski, Kelkheim, DE;
Leybold Aktiengesellschaft, Hanau, DE;
Abstract
A source (1) is equipped with a conveying device (4) for discharging the particles (2, 2a) at adjustable rates per unit time. A crystal (16), formed from doped particles, is withdrawn from the melting crucible (13) at a predetermined rate per unit time. So that the control process can be conducted smoothly over prolonged periods of time with precise doping, the particles (2, 2a) are fed single file to the melting crucible (13) and counted by at least one sensor (21, 22). The sequence of count pulses is sent to a counter (25) and compared there with a corresponding sequence of reference input pulses. The comparison signal formed from the count pulses and the reference input pulses is used, in accordance with its sign, as a control signal for adjusting the amount of particles being discharged per unit time from source (1) to correspond to the reference value.