Diodes and electromagnetic emmission Help?

AI Thread Summary
Determining the appropriate dopants for a diode's pn junction to achieve a specific electromagnetic wavelength is not straightforward, as no accurate model exists for this process. The industry typically relies on empirical methods, where researchers create numerous batches with varying dopants and concentrations, measuring the resulting LED spectra and compiling the data into tables. While selecting a dopant that creates an ion center at a specific energy level can help approximate the desired color, there is no precise formula for achieving an exact wavelength. The substrate material of the LED also significantly influences the emitted color. This information highlights the complexity and empirical nature of designing diodes for specific electromagnetic emissions.
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How would one go about figuring out what to dope a diodes pn junction with in order to create a desired electromagnetic wavelength ?
 
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You don't. My solid state professor told me that no one ever came up with an accurate model for this. He did his grad work on LED's.

What the industry did is to have grad students cook up thousands of batches with different dopants and concentrations. They then measured the spectrum of the resulting LED's and stored the data in tables. Somewhere there must be a book filled with tables for LED colors.

Edit:

You can get close to the color you want by selecting a dopant which creates an ion center at a specific energy level but there is no formula for getting an exact color.

My information may be out of date though. I took solid state physics about 10 years ago.
 
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Hey, I found a nice pdf on LED's with some basic tables for LED colors. The color largely depends on the LED substrate material itself.

Check it out here
 
@Okefenokee Great thank you, exactly what i was looking for
 
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