Patent ID: 9746514
Date: 2017-08-29
CPC Classifications: G01N,G01R,H01L

Claim:
1. An apparatus, comprising: a first probe configured for establishing an electrical connection with a surface of a first layer of a p-n junction, the established electrical connection covering an area of the surface of the first layer of the p-n junction optimized to minimize a lateral current; a second probe configured for electrically contacting both the first layer and a second layer forming the p-n junction; a measurement unit electrically connected to the first probe and the second probe, the measurement unit configured for measuring at least one of: a voltage between the first and second probes and a current between the first and second probes when the first and the second probes are stimulated; a guard loop configured for preventing the lateral current from the first probe; and wherein at least one of: a voltage and a current applied to the guard loop is adjustable based on a measured surface voltage differential between the first probe and the guard loop.