Abstract:
Semiconductor light-emitting devices are provided. The semiconductor light-emitting devices include a substrate and a crystal layer selectively grown thereon at least a portion of the crystal layer is oriented along a plane that slants to or diagonally intersect a principal plane of orientation associated with the substrate thereby for example, enhancing crystal properties, preventing threading dislocations, and facilitating device miniaturization and separation during manufacturing and use thereof.
Abstract:
A semiconductor nanocrystal heterostructure has a core of a first semiconductor material surrounded by an overcoating of a second semiconductor material. Upon excitation, one carrier can be substantially confined to the core and the other carrier can be substantially confined to the overcoating.
Abstract:
A method of growing a compound semiconductor layer includes epitaxially growing a III-V compound semiconductor layer including nitrogen (N) for as the Group V element on a front surface of a semiconductor substrate of cadmium telluride (CdTe). Therefore, the atoms of the crystal lattice of the III-V compound semiconductor layer are periodically lattice-matched with the atoms of the crystal lattice of the CdTe semiconductor substrate, whereby the III-V compound semiconductor layer is epitaxially grown with high crystalline quality.
Abstract:
A quantum effective device and its method of manufacture are disclosed, wherein said device comprises quantum well boxes composes of a semiconductor substrate and a compound semiconductor on the surface of the semiconductor substrate at least comprising a first and a second elemental component and a semiconductor overlayer overlying said quantum well boxes and the surface portion of the exposed semiconductor substrate and wherein the quantum well boxes have an epitaxially grown single crystal structure obtained by depositing fine droplets of liquid phase composed of the first elemental component on the surface of the semiconductor substrate in the heated state and then incorporating a second elemental component different from the first elemental component in said droplets.
Abstract:
Hg.sub.1-x Cd.sub.x Te, Hg.sub.1-x Zn.sub.x Te and other related II-VI ternary semiconductor compounds are important strategic materials for photovoltaic infrared detector applications. Liquid phase epitaxy employing a tellurium-rich molten nonstoichiometric solution is an accepted technology for thin film epitaxial crystal growth.This present invention describes a crystal growth process employing specially encapsulated graphite components which directly facilitate a high volume, high quality large area epitaxial layer production.
Abstract:
A process for making single-crystal mercury cadmium telluride layers by epitaxial growth on a cadmium telluride substrate, performed inside a reactor with two communication zones, kept at different and controlled temperatures. The growth solution is directly prepared inside the reactor by subjecting weighed cadmium and tellurium quantities and a mercury bath to a specific thermal cycle so that the mercury concentration in the solution is established by absorption from the vapor phase and is controlled by the lower temperature level.
Abstract:
A method for chemical vapor deposition of materials containing tellurium, such as cadmium telluride and mercury cadmium telluride, wherein the reactant source of the tellurium is a tellurophene or methyltellurol. These reactant sources have high vapor pressures, and the reactant source vapors emitted from the reactant sources have decomposition temperatures of less than about 300.degree. C., so that deposition may be accomplished at low temperatures of about 250.degree. C. The reactant source vapor containing tellurium is mixed with a reactant source vapor containing another substance to be codeposited, such as dimethylcadmium or dimethylmercury, and contacted with a substrate maintained at the deposition temperature, the deposition being preferably accomplished in an inverted vertical chemical vapor deposition reactor.
Abstract:
A layer of Cd.sub.x Hg.sub.1-x Te is grown on a substrate by growing layers of HgTe t.sub.1 thick, and CdTe t.sub.2 thick alternately. The thicknesses t.sub.1 and t.sub.2 combined are less than 0.5 .mu.m so that interdiffusion occurs during growth to give a single layer of Cd.sub.x Hg.sub.1-x Te. The HgTe layers are grown by flowing a Te alkyl into a vessel containing the substrate and filled with an Hg atmosphere by an Hg bath. The CdTe layers are grown by flowing of Cd alkyl into the vessel where it combines preferentially with the Te on the substrate. Varying the ratio of t.sub.1 to t.sub.2 varies the value of x. Dopants such as alkyls or hydrides of Al, Ga, As and P, or Si, Ge, As and P respectively may be introduced to dope the growing layer.
Abstract:
Method for growing HgCdTe (15) upon a CdTe substrate (5) using a HgTe source (3) and close-spaced vapor phase epitaxy (CSVPE). A processing temperature T of between 520.degree. C. and 625.degree. C. is employed over a processing time t of between approximately 1/4 and 4 hours. The thickness A of the grown HgCdTe (15) is a linear function of processing time t. The mole fraction x of cadmium in the HgCdTe (15) is a linear function of temperature T and an exponential function of the mole fraction y of mercury in the source (3). The lower the relative amount of mercury in the source (3), the greater the relative amount of mercury in the end product (15), and vice versa. Any crystal plane and any axial orientation of the CdTe substrate (5) can be used without affecting the rate of growth of the HgCdTe (15), the single crystal nature of the HgCdTe (15), or the mirror-like finish of its surface. At least 90% of the transition between the CdTe substrate (5) and the grown HgCdTe layer (15) occurs within the first 20% of the HgCdTe layer (15); for distances greater than this away from the substrate (5), the HgCdTe (15) exhibits a substantially uniform x.
Abstract:
A method for producing a heterogeneous semiconductor structure with a composition gradient in which a semiconductor material is transferred through the gaseous phase onto the substrate from a source comprising the two AB and AC components and including a number of parallel strips, each of said strips having a constant ratio between the AB and AC components. At first, the source is gradually brought under the substrate at a speed chosen within the range of 100 cm per hour to 0.1 cm per hour, bringing first the strip of the source, which has a maximum content of the AB component. As all the strips have been brought under the substrate, the source is stopped for a period of time required for the formation of the main layer of a required thickness.