Question
Download Solution PDFThe basic material for fabrication of an LED is
Answer (Detailed Solution Below)
Detailed Solution
Download Solution PDFGenerally, optical devices are fabricated using direct bandgap semiconductors like GaAs and normal PN diode is fabricated by using Si. The most basic material for the fabrication of an LED is GaAs (Gallium Arsenide).
Using GaAs as basic material, GaAs produces LEDs of different colors. This is as shown:
|
Semiconductor material |
Wavelength |
Colour |
|
GaAs |
850 – 940 nm |
Infra-red |
|
GaAsP |
630 – 660 nm |
Red |
|
GaAsP |
605 – 620 nm |
Amber |
|
GaAsP:N |
585 – 595 nm |
Yellow |
|
AlGaP |
550 – 570 nm |
Green |
|
SiC |
430 – 505 nm |
Blue |
|
GaInN |
450 nm |
White |
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