Overview
This apparatus designed a micro current power supply to be used as the forward current of the PN junction. By adjusting the micro current to obtain the forward voltage drop across the PN junction, this can effectively avoid the instability of the measured micro current and accurately measure the forward voltage drop. A temperature control device is designed to obtain the volt-ampere characteristic curve of the PN junction at different temperatures, and the relationship between the PN junction voltage, current and temperature is studied, from which the Boltzmann constant k, the sensitivity S and the forbidden bandwidth of the silicon material are obtained.
Principle
The physical properties of semiconductor PN junctions are an important foundation of semiconductor physics. Using this apparatus, the relationship between the PN junction diffusion current and the voltage can be studied. Students can also learn that this relationship follows the exponential distribution law, and the physics important constant, the Boltzmann constant, can be measured accurately.
At the mean time, the relationship between the PN junction voltage and the thermodynamic temperature can also be measured. With thisrelationship, students can get the sensitivity S of the temperature sensor which made by PN junction. Further, the temperature 0 K's forbidden bandwidth of the silicon material can be obtained approximately.
Experiments and Typical Results
1. Measure the IF - Ube curve at room temperature
2. Measure the Ube - T curve
The results obtained by digital experiment
Parts List
BEM-5714 PN Junction Characteristic & Boltzmann Constant Controller
BEM-5051 Temperature Control Power Supply II
BEM-5052 PN Junction Heating Device
BEM-5053 PN Junction Probe
Options
UI-5001 550 universal data acquisition interface
UI-5400 Capstone data acquisition software
PS-3211 Wireless voltage sensor (2)
Packinglist
Apparatus x 1; Power cord x 2; Connection cable x 5; Sheathed banana plug cable x 2; Manual x1