摘要:
An epitaxial structure for a III-Nitride based optical device, comprising an active layer with anisotropic strain on an underlying layer, where a lattice constant and strain in the underlying layer are partially or fully relaxed in at least one direction due to a presence of misfit dislocations, so that the anisotropic strain in the active layer is modulated by the underlying layer.
摘要:
A light emitting diode (LED) having a p-type layer having a thickness of 100 nm or less, an n-type layer, and an active layer, positioned between the p-type layer and the n-type layer, for emitting light, wherein the LED does not include a separate electron blocking layer.
摘要:
A method of fabricating an optoelectronic device, comprising growing an active layer of the device on an oblique surface of a suitable material, wherein the oblique surface comprises a facetted surface. The present invention also discloses a method of fabricating the facetted surfaces. One fabrication process comprises growing an epitaxial layer on a suitable material, etching the epitaxial layer through a mask to form the facets having a specific crystal orientation, and depositing one or more active layers on the facets. Another method comprises growing a layer of material using a lateral overgrowth technique to produce a facetted surface, and depositing one or more active layers on the facetted surfaces. The facetted surfaces are typically semipolar planes.
摘要:
A method for improving the growth morphology of (Ga,Al,In,B)N thin films on nonpolar or semipolar (Ga,Al,In,B)N substrates, wherein a (Ga,Al,In,B)N thin film is grown directly on a nonpolar or semipolar (Ga,Al,In,B)N substrate or template and a portion of the carrier gas used during growth is comprised of an inert gas. Nonpolar or semipolar nitride LEDs and diode lasers may be grown on the smooth (Ga,Al,In,B)N thin films grown by the present invention.
摘要:
The present invention provides a method for growing group III-nitride crystals wherein the group III-nitride crystal growth occurs on an etched seed crystal. The etched seed is fabricated prior to growth using a temperature profile which produces a high solubility of the group III-nitride material in a seed crystals zone as compared to a source materials zone. The measured X-ray diffraction of the obtained crystals have significantly narrower Full Width at Half Maximum values as compared to crystals grown without etch back of the seed crystal surfaces prior to growth.
摘要:
A high-power and high-efficiency light emitting device with emission wavelength (λpeak) ranging from 280 nm to 360 nm is fabricated. The new device structure uses non-polar or semi-polar AlInN and AlInGaN alloys grown on a non-polar or semi-polar bulk GaN substrate.
摘要:
A technique for growing high quality bulk hexagonal single crystals using a solvo-thermal method, and a technique for achieving the high quality and high growth rate at the same time. The crystal quality strongly depends on the growth planes, wherein a nonpolar or semipolar seed surface such as {10-10}, {10-11}, {10-1-1}, {10-12}, {10-1-2}, {11-20}, {11-22}, {11-2-2} gives a higher crystal quality as compared to a c-plane seed surface such as (0001) and (000-1). Also, the growth rate strongly depends on the growth planes, wherein a semipolar seed surface such as {10-12}, {10-1-2}, {11-22}, {11-2-2} gives a higher growth rate. High crystal quality and high growth rate are achievable at the same time by choosing the suitable growth plane. The crystal quality also depends on the seed surface roughness, wherein high crystal quality is achievable when the nonpolar or semipolar seed surface RMS roughness is below 100 nm; on the other hand, the crystal grown from the Ga-face or N-face results in poor crystal quality, even though grown from an atomically smooth surface.
摘要:
A nonpolar III-nitride film grown on a miscut angle of a substrate. The miscut angle towards the direction is 0.75° or greater miscut and less than 27° miscut towards the direction. Surface undulations are suppressed and may comprise faceted pyramids. A device fabricated using the film is also disclosed. A nonpolar III-nitride film having a smooth surface morphology fabricated using a method comprising selecting a miscut angle of a substrate upon which the nonpolar III-nitride films are grown in order to suppress surface undulations of the nonpolar III-nitride films. A nonpolar III-nitride-based device grown on a film having a smooth surface morphology grown on a miscut angle of a substrate which the nonpolar III-nitride films are grown. The miscut angle may also be selected to achieve long wavelength light emission from the nonpolar film.
摘要:
Highly planar non-polar GaN films are grown by hydride vapor phase epitaxy (HVPE). The resulting films are suitable for subsequent device regrowth by a variety of growth techniques.
摘要:
An (Al, Ga, In)N light emitting device, such as a light emitting diode (LED), in which high light generation efficiency is realized by fabricating the device on non-polar or semi-polar III-Nitride crystal geometries. Because non-polar and semi-polar emitting devices have significantly lower piezoelectric effects than c-plane emitting devices, higher efficiency emitting devices at higher current densities can be realized.