Find Constant A in IV Diode Characteristic - Urgent Homework

[mack90mg]

Homework Statement

this is a lab task, i have found out the IV characteristic of the diode,

now they ask me to suggest a procedure to find the constant A, in the equation
I= AT^3 x exp (-E/ kT),
T being the temperature, and I = saturation current

Homework Equations

i know how to find ideality factor fron the the IV graph, but can I find 'A' from the IV graph ?
If not, then what other test equipment and procedures do i need to find 'A' ?
Is 'A' related to the intrinsic carrier concentration in any way?



its very urgent, so i ll really appreciate a prompt reply.
thanks :)

 

[LightHero]

The Attempt at a SolutionNo, you cannot find 'A' from the IV graph. To find the constant 'A', you need to use other test equipment such as a thermocouple or a temperature probe. You can measure the saturation current (I) at different temperatures and then plot the graph of I vs T. From this graph, you can calculate the value of 'A'. Yes, 'A' is related to the intrinsic carrier concentration in the diode. It is proportional to the intrinsic carrier concentration and it increases with increasing temperature.

 

[piercas]

my response to this content would be as follows:

Hello, thank you for reaching out for assistance with your lab task. It is great that you have already found the IV characteristic of the diode. In order to find the constant A in the given equation, you can use the following procedure:

1. Use the IV characteristic graph to determine the saturation current (I) at different temperatures (T).

2. Plot a graph of ln(I) vs 1/T. This will give you a straight line with a slope of -E/k (where E is the energy gap of the diode and k is the Boltzmann constant).

3. Use the slope value to calculate the value of E.

4. Use the known value of E to calculate the constant A using the equation A = I/(T^3 x exp(-E/kT)).

5. Repeat this process for different temperatures to get a range of values for A, and then take the average.

As for your question about the intrinsic carrier concentration, yes, the constant A is related to it. The intrinsic carrier concentration is given by ni = (A/kT)^2, so by finding A, you can also determine the intrinsic carrier concentration.

I hope this helps and I wish you the best of luck with your lab task. Please let me know if you have any further questions or need any clarification. Thank you.