Experimental characterization of the photovoltaic effect on different inorganic light emitting diode

This article describes an experimental work on the electrical characterization of commercial LEDs of different colors and photoelectric effect. This experiment was conducted at the IMS bordeaux (Laboratory of hardware... [ view full abstract ]

This article describes an experimental work on the electrical characterization of commercial LEDs of different colors and photoelectric effect. This experiment was conducted at the IMS bordeaux (Laboratory of hardware integration of the system) on a test bench for the intrinsic characterization of various light emitting diodes in forward and reverse bias. This bench is used to compare the experimental values with the theoretical values obtained with the model results. A second work in the ENP El Harrach has allowed us to develop measurement means to show that there is a photovoltaic effect on LEDs. For this, we measured the electrical characteristics of and studied their light intensities using a pyranometer EPLEY.

Concerning the photovoltaic effect, some research work has been done regarding this aspect; this is due to the fact that LEDs are made of a PN junction which is not opaque, the photons may reach and thereby produce a photovoltaic effect, like in the junctions case of a conventional solar cell. This work concerned LED red, green and yellow. In addition, we have also set up at The Laboratory of Integrated Systems based Sensors (LSIC) of the École Normale Supérieure (ENS)

 a device that measures the sensitivity of various LED based on the power of the source light illumination. The basic principle is to measure the variation of current as a function of the voltage applied through a temperature controlled by the LED. The diagram of the bench illustrated in Figure 1 by radius [1] temperature controlled by the bench and the outdoor temperature of the assembly of the LED. 

1-The main equipment used in the first experiment is: The semiconductor settings KEITHLEY 6430 analyzer connected by an IEEE bus connected to the CPU of the control computer. This device comprises a current source

10 ^ (- 16) A 0.1 A 10 ^ (- 17) A resolution (error 0.1%) and a voltage source (0 to 10 V) resolution 10 ^ (- 10) V (error 0.1%).

2- Pyranometer EPLEY is the element that measures the light intensity for the second manipulation.

3- A digital multimeter used in ammeter to measure the current across the yellow and red LED according to the power of illumination of a light source.