Lee, Gregg A.
Texas Instruments Incorporated, Dallas, Texas
Pages: 20 Published: Jan 1974
Spreading resistance measurements provide a highly flexible technique for the determination of dopant profiles in semiconductors. However, because each measurement samples a greater depth into the sample than the depth difference between successive measurements, the direct conversion of resistivity readings to dopant concentration values will not yield a correct profile. The technique discussed in this report analyzes direct spreading resistance readings to deduce a “true” dopant profile. The model used is that of circular contacts to a laterally infinite medium which is partitioned vertically into layers of homogeneous resistivity, each layer corresponding to one spreading resistance measurement point. The analysis is performed by a computer program. Some detail in the development of the program is discussed. The results of this analysis technique compare favorably to profile results of other profiling techniques such as capacitance voltage and incremental sheet resistance on profile types to which they can be applied. The program execution time is usually fast enough that the computer charge is less than the direct charge billed for making the spreading resistance measurements.
Correction factors, computer modeling, dopant profiles, multilayer spreading resistance model, resistivity, semiconductor dopant concentration, spreading resistance
Paper ID: STP47396S