I've been assigned a piece of work involving finding the temperature
coefficient of  a trace on an IC die.  The trace is ti-w and I'm using some
pretty sophisticated test equipment.  (I can't give too much info because
it's a process at the company where I work) I insert a signal at 100mV and
measure I.  I use these in ohm's law to find the resistance.  I do this at
increasing temperatures.  The problem I'm having is that the resistance
values are all over the ballpark.  They show an increase in resistance
linearly with temperature, but, not unless I average the results.  Even
then, I get anomalies in the slope.  Is there a formula to figure the
temperature coefficient of the ti-W at different ratios of ti to W?