Long life operations over 5000 hours of BeZnSeTe/MgZnCdSe visible light emitting diodes on InP substrates

Abstract

Aging characteristics of BeZnSeTe yellow light emitting diodes (LEDs) fabricated on InP substrates by molecular beam epitaxy were investigated under direct current injections at room temperature. It was shown that the decay speed of the light output during the aging was slower than that of conventional ZnCdSe/MgZnSSe LEDs. A long lifetime more than 5000 h and a half lifetime of 5180 h were obtained at a current density of 130 A/cm 2 . The half lifetimes of the BeZnSeTe LEDs were about three orders of magnitude greater than that of the ZnCdSe/MgZnSSe LEDs. These results proved high reliability of the BeZnSeTe LED. Investigating the aging characteristics of the applied voltage, the injection current, and the emission spectra showed that the output decay was caused by degradation of the active layer of the LEDs.

First photopumped yellow–green lasing operation of BeZnSeTe/(MgSe/BeZnTe) doublehetero structures (DHs) grown on InP substrates

“…ZnSebased materials, such as ZnSSe and MgZnSSe, grown on GaAs substrates have been investigated for blue-green laser diodes (LDs); then room-temperature (RT) continuous-wave (CW) lasing was reported for ZnCdSe/MgZnSSe LDs [1,2]. However, the device lifetimes of the LD was tested to be too short for practical use; the lifetime was limited to be approximately 400 h. At the same time, we developed other II-VI compound semiconductors such as MgZnCdSe, BeZnTe, and BeZnSeTe grown on InP substrates for yellow-to-green LDs and light-emitting diodes (LEDs) [3,4]. MgZnCdSe can be used for n-cladding layers because it has wide bandgap energies from 2.1 to 3.8 eV and a high n-doping property.…”

“…It contributes to strengthening the lattice bonds of BeZnSeTe [5], leading to a lengthening of the device lifetime. In fact, we have fabricated yellow/green LEDs with a BeZnSeTe active layer and a long lifetime of over 5000 h [4].…”

Zn irradiation effects in MBE growth of MgSe/BeZnSeTe II–VI compound superlattices on InP substrates

“…Visible emissions from 543 to 595 nm were observed. Long lifetime (more than 5000 h) operations were achieved on 575-nm LEDs [3]. These suggest that BeZnSeTe is promising for active layers of visible devices.…”

“…BeZnSeTe II-VI quaternaries on InP substrates are very attractive for middle visible range, i.e., yellow-to-green laser diodes (LDs) and light emitting diodes (LEDs) [1][2][3]. BeZnSeTe has direct bandgap energies (Eg) from 2.1 to 2.8 eV under lattice-matching to InP.…”

Application of indium tin oxide to the p‐cladding layers of yellow/green II‐VI compound semiconductor laser diode structures on InP substrates

“…BeZnTe/ZnSeTe SLs exhibit bandgap energies ranging from 2.11 to 2.48 eV, corresponding to the wavelength range from 500 to 585 nm under the lattice-matching with InP [12]. In addition, the SLs include BeTe, which is very effective for enhancing the device reliability (i.e., the device lifetime), with highly covalent bonds because of the strengthened lattice bonds [9,14]. On the other hand, MgSe/ZnCdSe SLs are suitable for the n-cladding layer because of their wide bandgap (approximately 3 eV) and high n-type doping property.…”