摘要:
A semiconductor light emitting element with a design wavelength of », comprising a photonic crystal periodic structure having two structures with different refractive indices at each of one or more interfaces between layers that form the light emitting element. The period a and the radius R that are parameters of each of the one or more periodic structures and the design wavelength » satisfy Bragg conditions. The ratio (R/a) between the period a and the radius R is a value determined so that a predetermined photonic band gap (PBG) for TE light becomes maximum for each periodic structure. The parameters of each periodic structure are determined so that light extraction efficiency of the entire semiconductor light emitting element with respect to light with the wavelength » becomes maximum as a result of conducting a simulation analysis with a FDTD method using as variables the depth h of the periodic structure that is of greater than or equal to 0.5a and the period a and the radius R that are determined for each order m of the Bragg conditions.
摘要:
A deep ultraviolet LED with a design wavelength of » is provided that includes a reflecting electrode layer, a metal layer, a p-type GaN contact layer, and a p-type AlGaN layer that are sequentially stacked from a side opposite to a substrate, the p-type AlGaN layer being transparent to light with the wavelength of »; and a photonic crystal periodic structure that penetrates at least the p-type GaN contact layer and the p-type AlGaN layer. The photonic crystal periodic structure has a photonic band gap.
摘要:
Provided is a deep ultraviolet LED with a design wavelength », including an Al reflecting electrode layer, an ultrathin metal layer, and a transparent p-AlGaN contact layer that are sequentially arranged from a side opposite to a substrate, and a photonic crystal periodic structure provided in the range of the thickness direction of the transparent p-AlGaN contact layer. The photonic crystal periodic structure has a photonic band gap.
摘要:
The light extraction efficiency of a deep ultraviolet LED is increased. The deep ultraviolet LED has a design wavelength », and includes, sequentially arranged from a side opposite to a substrate, a reflecting electrode layer, a metal layer, a p-GaN contact layer, a p-AlGaN layer that is transparent to light with the wavelength », one of a multi-quantum barrier layer or an electron blocking layer, a barrier layer, and a quantum well layer. A thickness of the p-AlGaN layer is less than or equal to 100 nm. A reflecting photonic crystal periodic structure having a plurality of voids is provided in a region in a thickness direction including at least an interface between the p-GaN contact layer and the p-AlGaN layer such that the reflecting photonic crystal periodic structure does not extend beyond the p-AlGaN layer in a direction of the substrate. Maximum light extraction efficiency is obtained when a distance from end faces of the voids in the direction of the substrate to the quantum well layer is greater than or equal to a total thickness of the barrier layer and the multi-quantum barrier layer (or the electron blocking layer) and less than or equal to 80 nm, and a depth h of each void is less than or equal to a total thickness of the p-AlGaN layer and the p-GaN contact layer. The reflecting photonic crystal periodic structure has a photonic band gap that opens for TE polarized components. A period a of the photonic crystal periodic structure satisfies a Bragg condition with respect to light with the design wavelength ». An order m in a formula of the Bragg condition satisfies 1‰¤m‰¤5. Provided that a radius of each void is R, R/a with which the photonic band gap becomes maximum is satisfied.
摘要:
A plasma treatment apparatus includes a wafer transfer tray having a first surface and a second surface opposite to the first surface and configured to hold a wafer on the first surface, a cooling unit configured to cool the wafer transfer tray, a conductive supporter configured to support the second surface of the wafer transfer tray, and a double-surface electrostatic attractor configured to electrostatically attract the wafer to the first surface of the wafer transfer tray and electrostatically attract the supporter to the second surface of the wafer transfer tray.