Optimized GaAs∕AlGaAs light-emitting diodes and high efficiency wafer-fused optical up-conversion devices

Abstract

Achieving a high internal quantum efficiency in GaAs∕AlGaAs based light-emitting diodes (LEDs) for room-temperature operation at low current-density injection is crucial for applications such as optical up-converters based on the integration of LEDs and photodetectros. We report the experimental results as well as the theoretical analyses of the internal quantum efficiency of GaAs∕AlGaAs LEDs as a function of the p-doping concentration of the active region for low current injection operation. By optimizing the doping concentration, we have achieved a close to 100% internal quantum efficiency for room-temperature operation of LEDs in the low injection current-density range, i.e., around 0.1A∕cm2. An optical up-converter was fabricated using wafer-fusion technology by integrating the optimized GaAs∕AlGaAs LED with an InGaAs∕InP photodetector. The internal up-conversion quantum efficiency was measured to be 76%.

Near-infrared to visible light optical upconversion by direct tandem integration of organic light-emitting diode and inorganic photodetector

“…[1][2][3][4] The near infrared optical upconverters in the eye-safe region around 1.5 m are of particular interest because of its many potential applications such as night vision, range finding, homeland security, and semiconductor wafer inspection. [5][6][7][8][9] Monolithic integration of a detector and an emitter using direct epitaxial growth 1,5 or wafer fusion technique [6][7][8] has been demonstrated. In monolithic devices by direct epitaxial growth, the band gap difference between the active region of a light-emitting device and the active region of the photodetector is highly restricted due to stringent lattice-matching requirements imposed by the uninterrupted epitaxial growth of the various layers in the devices.…”

Infrared single photon detector based on optical up-converter at 1550 nm

“…Mature fabrication technology and compact structure of this device make it promising for large-scale application. Besides, the high internal up-conversion quantum efficiency 24 (~80%) of the up-converter offers new thinking and method to fabricate a high performance single photon detector at the wavelength of 1550 nm.…”

GaAs-based near-infrared up-conversion device fabricated by wafer fusion

“…To have broad response, an as-deposited sample is used in this study. The LED efficiency is crucial to the up-converter performance, and Ban et al [6] have optimised GaAs/AlGaAs LEDs for infrared up-conversion application. The LED used in this study was the optimised LED design of [6].…”

“…InP-based LEDs have very low internal quantum efficiencies of less than 1%. However, GaAs/AlGaAs LEDs are capable of high internal efficiencies of near 100% [6]. Therefore, NIR up-conversion devices with both PD and LED based on GaAs substrates are advantageous.…”

“…The most investigated NIR PD is the InGaAs photodiode based on an InP substrate, which can routinely reach a responsivity higher than 1 A/W. Since 2000, NIR up-conversion devices with InGaAs/InP PDs have been fabricated [5,6]. In addition to InP-based PDs, GaAs-based NIR PDs lattice matched to GaAs substrate are now able to cover the important 1.3-1.55 mm wavelength region, with responsivities comparable to InGaAs/InP photodiodes [7,8].…”