Automatic apparatus for measuring resistivity of semiconductors

Claim 1

APPARATUS FOR MEASURING RESISTIVITY DATA OF A SEMICONDUCTOR SPECIMEN, SAID APPARATUS COMPRISING: A BASE, SPECIMEN HOLDING MEANS SUPPORTED BY SAID BASE, A CARRIAGE MOUNTED FOR RELATIVE MOVEMENT WITH RESPECT TO SAID SPECIMEN HOLDING MEANS, DRIVE MEANS FOR EFFECTING SAID RELATIVE MOVEMENT BETWEEN SAID SPECIMENT HOLDING MEANS AND SAID CARRIAGE, LOCATION MEASURING MEANS LOCATED ON SAID BASE PLATE FOR MEASURING THE LOCATION OF SAID CARRIAGE WITH RESPECT TO SAID SPECIMEN, AT LEAST ONE PAIR OF PROBES LOCATED ON SAID CARRIAGE ADAPTED FOR CONTACT WITH SAID SPECIMEN, MEANS FOR PASSING A CONSTANT ELECTRICAL CURRENT THROUGH AT LEAST A PORTION OF SAID SPECIMEN, MEANS FOR MEASURING THE VOLTAGE DROP BETWEEN SAID PROBES WHEN SAID PROBES ARE IN CONTACT WITH SAID SPECIMEN, A FIRST CONTACT ELEMENT LOCATED ON SAID CARRIAGE CONTACTING SAID SPECIMEN AT A DESIRED POINT, A SECOND CONTACT ELEMENT SPACED FROM SAID FIRST CONTACT ELEMENT CONNECTED TO SAID CARRIAGE FOR SELECTIVELY CONTACTING SAID SPECIMEN AT A DIFFERENT DESIRED POINT, ACTUATING MEANS FOR MOVING SAID SECOND CONTACT ELEMENT INTO CONTACT WITH SAID SPECIMEN, AND POTENTIOMETER MEANS ELECTRICALLY CONNECTED TO SAID FIRST AND SECOND CONTACT ELEMENTS FOR PRODUCING AN OUTPUT SIGNAL REPRESENTATIVE OF THE SIZE OF SAID SPECIMEN.