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Hi Guys!
How's your week so far? Its Friday and the weekend is coming! I'm sure you have activities run up starting tonight. So have fun!
Just a short update from me. Today is a happy day for me and the research group. After spending months setting our our new lab facility for Metalorganic Chemical Vapor Deposition (MOCVD), we finally grew our first LED structure! And of all colors, we decided to challenge ourselves and grew the toughest one - green!!! Below are the photoluminescene pictures!
The emission from the LED epilayer is done by exciting the quantum wells QW (the stuff inside) with a laser source which is of higher energy. Since we are growing green LED, a higher energy source is e.g. blue laser. So we are actually shooting a blue laser onto the crystal surface, but it cannot be seen very well cos it is absorbed by the QW. The QW in turn re-emits green light! So the light you see is coming directly from the epilayer (wafer).
A better view with higher laser excitation power. This is the first stage of an LED. After which it will undergo fabrication to have it electrically pumped, instead of optical. Many hours of hard work finally paid off! Yeah....
Ok.. enough of the boring stuff.
Here is a joke on Bush administration tapping onto US phone conversations! My phone calls to u are all monitored!!
Check out the "MTV" here
How's your week so far? Its Friday and the weekend is coming! I'm sure you have activities run up starting tonight. So have fun!
Just a short update from me. Today is a happy day for me and the research group. After spending months setting our our new lab facility for Metalorganic Chemical Vapor Deposition (MOCVD), we finally grew our first LED structure! And of all colors, we decided to challenge ourselves and grew the toughest one - green!!! Below are the photoluminescene pictures!
The emission from the LED epilayer is done by exciting the quantum wells QW (the stuff inside) with a laser source which is of higher energy. Since we are growing green LED, a higher energy source is e.g. blue laser. So we are actually shooting a blue laser onto the crystal surface, but it cannot be seen very well cos it is absorbed by the QW. The QW in turn re-emits green light! So the light you see is coming directly from the epilayer (wafer).
A better view with higher laser excitation power. This is the first stage of an LED. After which it will undergo fabrication to have it electrically pumped, instead of optical. Many hours of hard work finally paid off! Yeah....
Ok.. enough of the boring stuff.
Here is a joke on Bush administration tapping onto US phone conversations! My phone calls to u are all monitored!!
Check out the "MTV" here