Diodes and electromagnetic emmission Help?

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    Diodes Electromagnetic
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Discussion Overview

The discussion centers around the doping of a diode's p-n junction to achieve a specific electromagnetic wavelength, particularly in the context of light-emitting diodes (LEDs). It explores the challenges and methodologies involved in this process, including industry practices and empirical data collection.

Discussion Character

  • Exploratory, Technical explanation, Debate/contested

Main Points Raised

  • One participant inquires about methods to determine appropriate dopants for achieving desired electromagnetic wavelengths in diodes.
  • Another participant asserts that no accurate model exists for this process, citing their professor's experience and the reliance on empirical data from numerous experiments with various dopants and concentrations.
  • This participant mentions that while it is possible to select dopants to approximate a desired color by targeting specific energy levels, there is no formula for achieving an exact wavelength.
  • A third participant shares a resource with tables for LED colors, noting that the substrate material significantly influences the resulting color.
  • A later reply expresses gratitude for the shared resource, indicating it met their needs.

Areas of Agreement / Disagreement

Participants do not reach a consensus on a definitive method for doping diodes to achieve specific wavelengths, with multiple views on the effectiveness of empirical approaches versus theoretical models.

Contextual Notes

Limitations include the potential obsolescence of the information shared by one participant, as they mention their solid state physics knowledge is about 10 years old, and the reliance on empirical data rather than a theoretical framework for precise outcomes.

radaballer
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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.
 
Last edited:
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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