Corning Incorporated

Dmitry Sizov

Rajaram Bhat

Chung-En Zah

Jerome Napierala

Chad Stephen Gallinat

Group III nitride-based laser diodes comprise an n-side cladding layer formed of n-doped (Al,In)GaN, an n-side waveguide layer formed of n-doped (Al)InGaN, an active region, a p-side waveguide layer formed of p-doped (Al)InGaN, and a p-side cladding layer formed of p-doped (Al,In)GaN. Optical mode is shifted away from high acceptor concentrations in p-type layers through manipulation of indium concentration and thickness of the n-side waveguide layer. Dopant and compositional profiles of the p-side cladding layer and the p-side waveguide layer are tailored to reduce optical loss and increased wall plug efficiency.

Group III nitride-based green-laser diodes and waveguide structures thereof

Light emitting devices are provided comprising an active region interposed between n-type and p-type sides of the device and a hole blocking layer interposed between the active region and the n-type side of the device. The active region comprises an active MQW structure and is configured for electrically-pumped stimulated emission of photons in the green portion of the optical spectrum. The n-type side of the light emitting device comprises an n-doped semiconductor region. The p-type side of the light emitting device comprises a p-doped semiconductor region. The n-doped semiconductor region comprises an n-doped non-polar or n-doped semi-polar substrate. Hole blocking layers according to the present disclosure comprise an n-doped semiconductor material and are interposed between the non-polar or semi-polar substrate and the active region of the light emitting device. The hole blocking layer (HBL) composition is characterized by a wider bandgap than that of the quantum well barrier layers of the active region.

Hole blocking layers in non-polar and semi-polar green light emitting devices

According to the concepts of the present disclosure, laser diode waveguide configurations are contemplated where the use of Al in the waveguide layers of the laser is presented in the form of InGaN/Al(In)GaN waveguiding superstructure comprising optical confining wells (InGaN) and strain compensating barriers (Al(In)GaN). The composition of the optical confining wells is chosen such that they provide strong optical confinement, even in the presence of the Al(In)GaN strain compensating barriers, but do not absorb lasing emission. The composition of the strain compensating barriers is chosen such that the Al(In)GaN exhibits tensile strain that compensates for the compressive strain of InGaN optical confinement wells but does not hinder the optical confinement.

Strain balanced laser diode

A GaN-based edge emitting laser is provided comprising a semi-polar GaN substrate, an active region, an N-side waveguiding layer, a P-side waveguiding layer, an N-type cladding layer, and a P-type cladding layer. The GaN substrate is characterized by a threading dislocation density on the order of approximately 1&#xd7;10/cm. The strain-thickness product of the N-side waveguiding layer exceeds its strain relaxation critical value. In addition, the cumulative strain-thickness product of the active region calculated for the growth on a the relaxed N-side waveguiding layer is less than its strain relaxation critical value. As a result, the N-side interface between the N-type cladding layer and the N-side waveguiding layer comprises a set of N-side misfit dislocations and the P-side interface between the P-type cladding layer and the P-side waveguiding layer comprises a set of P-side misfit dislocations. Additional embodiments are disclosed and claimed.

GaN-based laser diodes with misfit dislocations displaced from the active region

Multi-quantum well laser structures are provided comprising active and/or passive MQW regions. Each of the MQW regions comprises a plurality of quantum wells and intervening barrier layers. Adjacent MQW regions are separated by a spacer layer that is thicker than the intervening barrier layers. The bandgap of the quantum wells is lower than the bandgap of the intervening barrier layers and the spacer layer. The active region may comprise active and passive MQWs and be configured for electrically-pumped stimulated emission of photons or it may comprises active MQW regions configured for optically-pumped stimulated emission of photons.

MQW laser structure comprising plural MQW regions

A semiconductor laser device operable to emit light having a desired wavelength in the green spectral range. The semiconductor laser device may include a pumping source and a laser structure including a substrate, a first cladding layer, and one or more active region layers. The one or more active region layers include a number of quantum wells having a spontaneous emission peak wavelength that is greater than about 520 nm at a reference pumping power density. The pumping source is configured to pump each quantum well at a pumping power density such that a stimulated emission peak of each quantum well is within the green spectral range, and the number of quantum wells within the one or more active region layers is such that a net optical gain of the quantum wells is greater than a net optical loss coefficient at the desired wavelength in the green spectral range.

Native green laser semiconductor devices

Ga(In)N-based laser structures and related methods of fabrication are proposed where Ga(In)N-based semiconductor laser structures are formed on AlN or GaN substrates in a manner that addresses the need to avoid undue tensile strain in the semiconductor structure. In accordance with one embodiment of the present invention, a Ga(In)N-based semiconductor laser is provided on an AlN or GaN substrate provided with an AlGaN lattice adjustment layer where the substrate, the lattice adjustment layer, the lower cladding region, the active waveguiding region, the upper cladding region, and the N and P type contact regions of the laser form a compositional continuum in the semiconductor laser. Additional embodiments are disclosed and claimed.

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Corning, NY, United States of America

Dmitry Sizov