The role of extended and point defects, and key impurities such as C, O, and H, on the electrical and optical properties of GaN is reviewed. Recent progress in the development of high reliability contacts, thermal processing, dry and wet etching techniques, implantation doping and isolation, and gate insulator technology is detailed. Finally, the performance of GaN-based electronic and photonic devices such as field effect transistors, UV detectors, laser diodes, and light-emitting diodes is covered, along with the influence of process-induced or grown-in defects and impurities on the device physics.

Gan : processing, defects, and devices

Recent advances in fabrication technologies for the semiconducting nitrides of the group III elements have led to commercially available, high-efficiency solid-state devices that emit green and blue light Light-emitting diodes based on these materials should find applications in flat-panel displays, and blue and ultraviolet laser diodes promise high-density optical data storage and high-resolution printing

Nitride-based semiconductors for blue and green light-emitting devices

During the last few years the developments in the field of III–nitrides have been spectacular. High quality epitaxial layers can now be grown by MOVPE. Recently good quality epilayers have also been grown by MBE. Considerable work has been done on dislocations, strain, and critical thickness of GaN grown on different substrates. Splitting of valence band by crystal field and by spin-orbit interaction has been calculated and measured. The measured values agree with the calculated values. Effects of strain on the splitting of the valence band and on the optical properties have been studied in detail. Values of band offsets at the heterointerface between several pairs of different nitrides have been determined. Extensive work has been done on the optical and electrical properties. Near band-edge spectra have been measured over a wide range of temperatures. Free and bound exciton peaks have been resolved. Valence band structure has been determined using the PL spectra and compared with the theoretically calcu...

III–nitrides: Growth, characterization, and properties

InGaN multi-quantum-well-structure laser diodes with Al0.14Ga0.86N/GaN modulation doped strained-layer superlattice cladding layers grown on an epitaxially laterally overgrown GaN (ELOG) substrate was demonstrated to have a lifetime of more than 1150 h under room-temperature continuous-wave operation. After 4 μm etching of the ELOG substrate, the etch pit density was about 2×108 cm2 in the region of the 4-μm-wide stripe window, but almost zero in the region of the 7-μm-wide SiO2 stripe.

InGaN/GaN/AlGaN-based laser diodes with modulation-doped strained-layer superlattices grown on an epitaxially laterally overgrown GaN substrate

A nitride semiconductor light-emitting device has an active layer of a single-quantum well structure or multi-quantum well made of a nitride semiconductor containing indium and gallium. A first p-type clad layer made of a p-type nitride semiconductor containing aluminum and gallium is provided in contact with one surface of the active layer. A second p-type clad layer made of a p-type nitride semiconductor containing aluminum and gallium is provided on the first p-type clad layer. The second p-type clad layer has a larger band gap than that of the first p-type clad layer. An n-type semiconductor layer is provided in contact with the other surface of the active layer.

Nitride semiconductor light emitting device

Room‐temperature cw operation for InGaP/InGaAlP double heterostructure (DH) laser diodes on GaAs substrates was achieved for the first time. The DH wafers were grown by low‐pressure metalorganic chemical vapor deposition using methyl metalorganics. A lasing wavelength of 679 nm and a threshold current of 109 mA at 24 °C were obtained for an inner stripe structure laser diode with a 250‐μm‐long and 7‐μm stripe geometry. The laser operated at up to 51 °C. The characteristic temperature T0 was 87 K at around room temperature. The lowest threshold current density, 5.0 kA/cm2, was obtained with a 20‐μm stripe width laser diode under room‐temperature pulsed operation.

Room temperature cw operation of InGaP/InGaAlP visible light laser diodes on GaAs substrates grown by metalorganic chemical vapor deposition

A method for manufacturing a light emitting device includes forming a multilayer body including a light emitting layer so that a first surface thereof is adjacent to a first surface side of a translucent substrate. A dielectric film on a second surface side opposite to the first surface of the multilayer body is formed having first and second openings on a p-side electrode and an n-side electrode. A seed metal on the dielectric film and an exposed surface of the first and second openings form a p-side metal interconnect layer and an n-side metal interconnect layer separating the seed metal into a p-side seed metal and an n-side seed metal by removing a part of the seed metal. A resin is formed in a space from which the seed metal is removed.

Light-emitting device and method for manufacturing same

We demonstrate room temperature pulsed operation of nitride based multi-quantum-well (MQW) laser diodes with cleaved mirror facets grown on a conventional C-face sapphire substrate. Cleavage was performed along the direction of the sapphire substrate, and the resultant facet was analyzed using an atomic force microscope (AFM) and theoretical calculation. A single peak emisson, at a wavelength of 417.5 nm, with a full width at half-maximum of 0.15 nm, was obtained. The threshold current density of the laser was 50 kA/cm2 and a voltage for the threshold current was 20 V.

https://iopscience.iop.org/article/10.1143/JJAP.35.L1315/pdf

Room Temperature Pulsed Operation of Nitride Based Multi-Quantum-Well Laser Diodes with Cleaved Facets on Conventional C-Face Sapphire Substrates

Nitride-based semiconductor element comprises a first layer, a mask formed on the first layer and has a plurality of opening portions, a nitride-based compound semiconductor layer formed on the mask, the nitride-based compound semiconductor layer including a first region having threading dislocations produced in such a manner that, in approximately a middle portion between two adjacent ones of the plurality of opening portions in the mask, a plurality of dislocations extend in a vertical direction to a surface of the mask, and a second region which comprises portions other than the middle portions and free from the dislocations, and a desired element structure formed on the semiconductor layer.

Masayuki Ishikawa

Papers

Room temperature cw operation of InGaP/InGaAlP visible light laser diodes on GaAs substrates grown by metalorganic chemical vapor deposition

Light-emitting device and method for manufacturing same

Room Temperature Pulsed Operation of Nitride Based Multi-Quantum-Well Laser Diodes with Cleaved Facets on Conventional C-Face Sapphire Substrates

Nitride-based semiconductor element and method for manufacturing the same

Growth of high-quality inGaAIP epilayers by MOCVD using methyl metalorganics and their application to visible semiconductors lasers