Transcript Resistance of Electronics as a function of Temperature

Electrical Resistance of
Semiconductors
and Temperature
And why our dream is relevant to real life…
A presentation by
Carolina Munoz
James Riley
Kam Tabattanon
Semiconductors
- Conductivity between a metal conductor and a
nonmetal insulator.
• Conductivity can be calibrated by altering the
chemical composition, adding impurities- “doping.”
- Unlike metal conductors, the electrical
resistivity of a semiconductor decreases with
increased temperature.
Two Modern Applications of
Semiconductors:
1. Solar cells
-Must function at a range of operating temperatures.
-Operating temperature affects material parameters
of semiconductors.
 Performance of solar cells changes as
resistance of semiconductors change with
operating temperature
2. Light Emitting Diodes
-Semiconductor light sources, many advantages
over incandescent sources.
-How does temperature change affect
semiconductor LEDs……?
Let’s do an experiment to find
out!!
• By constructing a simple circuit, and using
a constant voltage source and an
ammeter, the internal resistance over an
LED can be measured.
• Vary the operating temperature of the LED
• Measure the change in resistance of the
LED as a function of temperature by
measuring change in current.
• Test different LEDs at different voltages.
Questions to Research:
• How do semiconductors involved with LEDS differ from components in
different solar cells? Other applications?
• Do our results apply to other semiconductor types? Other applications?