[OPTICAL REVIEW Vol. 2, No. 3 (1995) 167-170]
High-Efficiency ZnCdSe/ZnSSe/ZnMgSSe Green Light-Emitting Diodes
Norikazu NAKAYAMA, Satoru KIJIMA, Satoshi ITOH, Toyoharu OHATA, Akira ISHIBASHI and Yoshifumi MORI
Sony Corporation Research Center, Fujitsuka-cho 174, Hodogaya-ku, Yokohama, 240 Japan
(Received February 10, 1995; Accepted March 20, 1995)
Green light-emitting diodes (LEDs) were fabricated employing a ZnCdSe/ZnSSe triple quantum-well (TQW) active region surrounded by ZnMgSSe cladding layers grown on an n-type (1 0 0) GaAs substrate by molecular beam epitaxy (MBE). A 3.5 mW pure green emission was observed for the surface-emitting LED device at a peak wavelength of 513.3 nm (2.415 eV) with a spectral half-width of 11.7 nm (55 meV) under a 20 mA (4.6 V) direct current at room temperature (25°C). These correspond to an external quantum efficiency of 7.2%, a power conversion efficiency of 3.8%, a luminous current efficiency of 66 lm/A, and a luminous efficiency of 14 lm/W.
Key words : ZnCdSe, ZnSSe, ZnMgSSe, ZnSe, ZnTe, high efficiency, green, LED