Computer Control of Surface Impurity by Spreading Resistance
Original Publication Date: 1984-Jan-01
Included in the Prior Art Database: 2005-Feb-02
The Spreading Resistance (Rsp) technique has been instrumental in the characterization of semiconductor devices by profiling. With the implementation of software-controlled calibration parameters, the technique may also be used to monitor the impurity concentration (Co) of an epitaxial layer on a real time basis in a manufacturing environment. There are two basic requirements for surface Co control by Rsp, namely, stabilized standards and reproducible probe point to silicon surface contacts. The standards which are used to create a calibration curve are epitaxial samples with various values of Co as determined by other techniques. Each sample is assigned a fixed Co value representative of the products being processed.