Building a Seebeck Meter for Determining Relative Nitrogen Doping Levels

Integrated Scientific Resources developed a Seebeck meter for measuring the nitrogen doping of a Tantalum Nitride film resistor.

The Seebeck coefficient is established by measuring the potential difference between the cold and hot junctions of the Seebeck apparatus (Trudel, 1972, Martin 2013).

Also measured are the pre- and post annealing sheet resistances using a four-point-probe. The Seebeck coefficient along with the sheet resistance measurements are used to determine the relative nitrogen levels.

The Cinco program measures the Seebeck voltage voltage using the Keithley 7510 7½ digitals multimeter.  The sheet resistance is measured across the four-point probe using he Keithley 2450 source measure instrument. The program establishes the desired thermal conditions using Love Controllers managed over serial RS485.

Figure 1. Shows the temperature controllers.

Figure 2. The Cinco program panel showing the measured sheet resistances and seebeck coefficient.
Trudel, M.L., Determination of the Relative Nitrogen Doping Level of Tantalum Nitride Resistor Film by Means of the Seebeck Effect. IEEE TRANSACTIONS ON Parts, Hybrids, and Packaging, vol. PHP-8, no. 3. September 1972.
Tektronix Corporation.,  Application note Number 3247: Resistivity Measurements Using the Model 2450 SMU Instrument and a Four-Point Collinear Probe,
Joshua Martin, Protocols for the high temperature measurement of the Seebeck coefficient in thermoelectric materials. Meas. Sci. Technol. 24 (2013)