Temperature Measurement Via Oxygen Donor Generation in Silicon
Original Publication Date: 1985-Apr-01
Included in the Prior Art Database: 2005-Feb-19
The following technique measures in situ temperatures (350ŒC to 520ŒC) by using silicon p type wafers with an oxygen concentration greater than 30 ppm and a resistivity of 30 to 60 ohm-cm. 1. Generate a standard curve of donor generation vs. temperature for a range of oxygen concentrations. 2. Characterize the wafers for resistivity and oxygen concentration. 3. Process through the thermal cycle of interest, e.g., plasma nitride deposition or LPCVD oxide deposition. 4. Recharacterize the wafers for resistivity and oxygen concentration. 5. Compute the delta in donor concentration from the curves generated by concentration at the surface vs. average conductivity. 6. The delta is the donor generation value used to enter the curve generated in step one, thus giving the temperature of the process in question.