Compensated-Strain Multiquantum-Well Active Layer for InGaAlP-Based Visible Light Emitting Diodes

Compensated-strain multiquantum-well (CS-MQW) structures have been investigated as the active region for InGaAlP-based visible light emitting diodes (LEDs). Strained layers for the LED active region were successfully grown by metalorganic chemical vapor deposition (MOCVD) with a compensated-strain structure. The total thickness of the strained active region was six times thicker than the critical thickness of the single strained layer. The precise control of a 20-quantum-well structure with tensile-strained wells and compressive-strained barriers was confirmed by X-ray diffraction measurements. A high-efficiency short-wavelength (585 nm) light emission was obtained for a current injection LED with the CS-MQW active region.