LED Colors and materials
Conventional LEDs are made from a variety of inorganic semiconductor materials, the following table shows the available colors with wavelength range, voltage drop and material:
| Color | Wavelength (nm) | Voltage (V) | Semiconductor Material | |
|---|---|---|---|---|
| Infrared | λ > 760 | ΔV < 1.9 | Gallium arsenide (GaAs) Aluminium gallium arsenide (AlGaAs) |
|
| Red | 610 < λ < 760 | 1.63 < ΔV < 2.03 | Aluminium gallium arsenide (AlGaAs) Gallium arsenide phosphide (GaAsP) Aluminium gallium indium phosphide (AlGaInP) Gallium(III) phosphide (GaP) |
|
| Orange | 590 < λ < 610 | 2.03 < ΔV < 2.10 | Gallium arsenide phosphide (GaAsP) Aluminium gallium indium phosphide (AlGaInP) Gallium(III) phosphide (GaP) |
|
| Yellow | 570 < λ < 590 | 2.10 < ΔV < 2.18 | Gallium arsenide phosphide (GaAsP) Aluminium gallium indium phosphide (AlGaInP) Gallium(III) phosphide (GaP) |
|
| Green | 500 < λ < 570 | 1.9[32] < ΔV < 4.0 | Indium gallium nitride (InGaN) / Gallium(III) nitride (GaN) Gallium(III) phosphide (GaP) Aluminium gallium indium phosphide (AlGaInP) Aluminium gallium phosphide (AlGaP) |
|
| Blue | 450 < λ < 500 | 2.48 < ΔV < 3.7 | Zinc selenide (ZnSe) Indium gallium nitride (InGaN) Silicon carbide (SiC) as substrate Silicon (Si) as substrate — (under development) |
|
| Violet | 400 < λ < 450 | 2.76 < ΔV < 4.0 | Indium gallium nitride (InGaN) | |
| Purple | multiple types | 2.48 < ΔV < 3.7 | Dual blue/red LEDs, blue with red phosphor, or white with purple plastic |
|
| Ultraviolet | λ < 400 | 3.1 < ΔV < 4.4 | diamond (235 nm)[33] Boron nitride (215 nm)[34][35] Aluminium nitride (AlN) (210 nm)[36] Aluminium gallium nitride (AlGaN) Aluminium gallium indium nitride (AlGaInN) — (down to 210 nm)[37] |
|
| White | Broad spectrum | ΔV = 3.5 | Blue/UV diode with yellow phosphor |