Multicolor light-emitting lamp and light source

A multicolor light-emitting lamp fabricated by disposing a plurality of LEDs by combining at least a blue light emitting diode (LED), a green LED and a red LED,

• wherein the blue LED comprises a low-temperature buffer layer composed of an amorphous or polycrystalline boron-containing group III-V compound semiconductor and provided on an electrically conducting substrate surface, a lower barrier layer composed of a boron phosphide (BP)-base group III-V compound semiconductor containing boron (B) and phosphorus (P) and provided on the low-temperature buffer layer, a light-emitting layer composed of a group III-V compound semiconductor and provided on the lower barrier layer, and an upper barrier layer composed of a boron phosphide-base group III-V compound semiconductor formed on the light emitting layer,
• wherein the green LED is a hetero-junction type LED of emitting green band light and comprises a light-emitting layer provided on a single crystal substrate and an upper barrier layer composed of a boron phosphide-base group III-V compound semiconductor layer and provided on the light-emitting layer,
• wherein the red LED is a hetero-junction type LED of emitting red band light and comprises a light-emitting layer provided on a single crystal substrate and an upper barrier layer composed of a boron phosphide-base group III-V compound semiconductor layer and provided on the light-emitting layer,
• wherein each of the LEDs for providing the multicolor light emitting lamp is formed on an upper surface of a single crystal substrate having the same conduction type,
• wherein a back-surface ohmic electrode having a first polarity is provided on a lower surface of the single crystal substrate of each of the LED, and
• wherein a front-surface ohmic electrode having a second polarity opposite to said first polarity is provided on a side of each of the LEDs opposite the back-surface ohmic electrode.