Abstract:
A method for fabrication of defect-free epitaxial layers on top of a surface of a first defect-containing solid state material includes the steps of selective deposition of a second material, having a high temperature stability, on defect-free regions of the first solid state material, followed by subsequent evaporation of the regions in the vicinity of the defects, and subsequent overgrowth by a third material forming a defect-free layer.
Abstract:
The present invention creates oxide and air apertures in material systems, such as InP, that do not usually accommodate epitaxial incorporation of highly oxidizing materials, such as AIAs, of sufficient thickness to adequately provide optical as well as current aperturing. A composite structure of relatively slowly oxidizing layer or layers (e.g. AllnAs on InP) with a faster-oxidizing layer or layers (e.g. AIAs on InP) can be used to produce oxide and air apertures of various shapes and sizes, and to also increase the oxidation rate.
Abstract:
The invention relates to an assembly of stacked semiconductor laser diodes, arranged on a substrate (1). A first laser diode (12) is positioned on the substrate (1) and a second laser diode (13) is positioned on top of the first laser diode (12). A contact layer (6) is located between the first laser diode (12) and the second laser diode (13). The contact layer (6) comprises a first conductive layer (18) of a first conductivity type, a second conductive layer (20) of a second conductivity type and an intermediate layer (19), which is located between the first and the second conductive layers (18, 20).
Abstract:
An improved semiconductor structure is provided. The semiconductor structure comprises a first layer, the first layer having a restricted growth surface having a region with a transverse dimension D, the first layer having a first lattice constant L1; a first, last and at least one intermediate transition layers, the transition layers forming a transition region, the transition region disposed above the first layer, the transition region having a vertical tickness T, and where at least one of the transition layers has lattice constants between L1 and a second lattice constant L2 where the first transition layer has a lattice constant closer to the L1 than L2 and the last transition layer has a lattice constant closer to the L2 than L1; and a second layer disposed on the transition region, the second layer having the second lattice constant L2; wherein: the transition region has an average fractional change in lattice constant characterized by kappa where kappa = (D/T) {(L2 - L1)/L1}, where 0 /=2 mu m.
Abstract:
A semiconductor laser is provided at least with an active layer and a saturable absorption layer and the amount of compressive strain of the absorption layer is set about 0.3 % or more larger than that of the active layer. Alternatively, the semiconductor laser is provided at least with the active layer, saturable absorption layer, and a light guide layer arranged near the absorption layer and the amount of compressive strain of the absorption layer is about 0.3 % or larger than that of the active layer.
Abstract:
TYPE-II semiconductor heterojunction light emitting devices formed on a substrate (10) are described wherein a graded injection layer (18) is used to accelerate electrons over the electron barrier formed by the junction. Further, wide band gap semiconductor LEDs and lasers are proposed formed of II-VI materials which emit light in the blue and green wavelengths. Particularly, a system composed of n-CdSe:A1/MgxCd1-xSe/MgyZn1-yTe/p-ZnTe are described where the value of y determines the wavelength of the emitted light in the green or blue region and x varies across the graded injection layer for raising the energy levels of excited electrons.
Abstract:
A semiconductor vertical light source includes an upper mirror and a lower mirror. An active region is between the upper and lower mirror. The light source includes an inner mode confinement region and outer current blocking region. The outer current blocking region includes a common epitaxial layer that includes an epitaxially regrown interface which is between the active region and upper mirror, and a conducting channel including acceptors is in the inner mode confinement region. The current blocking region includes a first impurity doped region with donors between the epitaxially regrown interface and active region, and a second impurity doped region with acceptors is between the first doped region and lower mirror. The outer current blocking region provides a PNPN current blocking region that includes the upper mirror or a p-type layer, first doped region, second doped region, and lower mirror or an n-type layer.
Abstract:
Eine Halbleiterlaserdiode weist eine Schichtenfolge auf, die eine Mehrzahl in einer Wachstumsrichtung übereinander angeordneter Schichten umfasst. Die Halbleiterlaserdiode weist eine Spiegelfacette und eine Auskoppelfacette auf, zwischen denen ein sich in eine longitudinale Richtung erstreckender Resonator gebildet ist. Die Schichtenfolge umfasst eine aktive Schicht, in der ein aktiver Bereich ausgebildet ist. Die Schichtenfolge umfasst eine in Wachstumsrichtung oberhalb der aktiven Schicht angeordnete verspannte Schicht.
Abstract:
Externally-strained devices such as LED and FET structures as discussed herein may have strain applied before or during their being coupled to a housing or packaging substrate. The packaging substrate may also be strained prior to receiving the structure. The strain on the devices enables modulation of light intensity, color, and electrical currents in some embodiments, and in alternate embodiments, enables a fixed strain to be induced and maintained in the structures.