Broad-spectrum A1(1-x-y)InyGaxN light emitting diodes and solid state white light emitting devices

摘要

A broad-spectrum Al_(1-x-y)In_yGa_xN light emitting diode (LED), including: a substrate, a buffer layer, an N-type cladding layer, at least one quantum dot emitting layer, and a P-type cladding layer. The buffer layer is disposed over the substrate. The N-type cladding layer is disposed over the buffer layer to supply electrons. The quantum dot emitting layer is disposed over the N-type cladding layer and includes plural quantum dots. The dimensions and indium content of the quantum dots are manipulated to result in uneven distribution of character distribution of the quantum dots so as to increase the FWHM of the emission wavelength of the quantum dot emitting layer. The P-type cladding layer is disposed over the quantum dot emitting layer to supply holes. A broad-spectrum Al_(1-x-y)In_yGa_xN yellow LED may thus be made from the LED structure of this invention, with an emission wavelength at maximum luminous intensity falling within a range of 530~600 nm, and FWHM within a range of 20~150 nm. After packaging an Al_(1-x-y)In_yGa_xN blue LED to form a solid state white light emitting device, the mixing of blue light and yellow light would generate white light with a high CRI index, high luminous intensity and capable of various color temperature modulation.