Abstract: Disclosed is a method of forming a quantum dots array. In the method of the present invention, a structure of wire-like quantum dots with good quality is formed in materials having an inconsistency in the lattice constant on a tilted substrate by using the binding property of atomic bonding due to chemical bonding steps of the tilted substrate, and the spacing of the wire-like quantum dots is varied by using the step width of the tilted substrate which is transformed due to a partial pressure of a source gas and the thickness of a buffer layer. The invention allows materials having an inconsistency in the lattice constant to be freely formed in the form of quantum wires with a growing technique only and accordingly to be used as base materials in use for manufacture of novel concept of optoelectronic devices which have not been obtained so far.

Abstract: Disclosed is a method for forming a nano-crystal. In the above method, there is prepared a substrate having a metal film or a semiconductor film formed thereon. A focused-ion beam is irradiated onto a plurality of positions on a surface of the metal film or the semiconductor film, whereby the metal film or the semiconductor film is removed at a focal portion of the focused-ion beam but an atomic bond in the metal film or the semiconductor film is broken at an overlapping region of the focused-ion beams due to an radiation effect of the focused-ion beam to form the nano-crystal. The method allows a few nm or less-sized nano-crystals to be formed with ease and simplicity using the focused-ion beam. As a result, the formed nano-crystals come to have a binding energy capable of restraining thermal fluctuation phenomenon at room temperature and thereby it becomes possible to fabricate a tunneling transistor capable of being operated at room temperature.

Abstract: Disclosed is a method for fabricating a single electron tunneling transistor. In the above method, an insulating layer and a conductive layer are orderly formed on a substrate. The conductive layer is patterned such that the insulating layer is exposed, to form a T-shaped conductive pattern of which a first portion arranged in a vertical direction is connected to a middle portion of a second portion arranged in a horizontal direction. A focused-ion beam is irradiated onto the connected middle portion of the T-shaped conductive pattern such that the second portion is cut at a middle portion thereof and the first portion is separated from the first portion, to form nano-crystal regions respectively at a first cut portion of the first pattern and a second cut portion of the second pattern using an irradiation effect of the focused-ion beam.

Abstract: The present invention relates to a method of fusion for heteroepitaxial layers and overgrowth thereon. According to the present invention, a high quality heteroepilayer can be formed by patterning a fused semiconductor layer, overgrowing it with a persistent patterned character, and fusing other semiconductors having different lattice constants by means of utilizing the rate difference between the lateral growth rate and the vertical growth rate exhibited, on the above process. Further, according to the present invention, the lattice constant difference of the two semiconductors can be overcome and a high quality quantum structure can be formed. According to the present invention, the junction of two semiconductor materials having different lattice constants, as well as a good overgrowth on heteroepitaxial layers can be carried out. Accordingly to the present invention, the base material from which the new, as yet on realized, conceptive optoelectronic device can be made.

Abstract: Disclosed is a method for forming a nano-crystal. In the above method, there is prepared a substrate having a metal film or a semiconductor film formed thereon. A focused-ion beam is irradiated onto a plurality of positions on a surface of the metal film or the semiconductor film, whereby the metal film or the semiconductor film is removed at a focal portion of the focused-ion beam but an atomic bond in the metal film or the semiconductor film is broken at an overlapping region of the focused-ion beams due to an radiation effect of the focused-ion beam to form the nano-crystal. The method allows a few nm or less-sized nano-crystals to be formed with ease and simplicity using the focused-ion beam. As a result, the formed nano-crystals come to have a binding energy capable of restraining thermal fluctuation phenomenon at room temperature and thereby it becomes possible to fabricate a tunneling transistor capable of being operated at room temperature.

Abstract: A method for aligning quantum dots effectively controls a growth position of the quantum dots for obviating an irregularity of a position of spontaneous formation quantum dots, and thus aligns the quantum dots in one-dimension (1-D) or two-dimension (2-D). A semiconductor device fabricated using the method manufactures a superlattice layer layer for adjusting an internal strain distribution by alternately depositing two semiconductor materials having different lattice constant, and grows spontaneous formation quantum dots on the superlattice layer. As a result, a strained force caused by the superlattice layer influences on the quantum dots so that the quantum dots can be regularly aligned.

Abstract: A quantum wire laser diode fabrication method includes the steps of forming a buffer layer and an epitaxial layer sequentially on a substrate, forming a V-grooved pattern into the epitaxial layer to form a current blocking layer, and forming another buffer layer thereon, forming a quantum wire laser structure on the V-grooved pattern, forming a contact layer, and forming an electrode. The fabrication method employs a current blocking layer formed outside the V-grooved pattern to interrupt the current from flowing thereinto, for thereby enabling the current to only flow into the active layer, without requiring any subsequent processes which allow the current to efficiently flow into the active layer, and further obtaining the low threshold current.

Abstract: A fabrication method for a horizontal direction semiconductor PN junction array which can be achieved when an epitaxial layer is grown by a metalorganic chemical vapor deposition (MOCVD method) by introducing (or doping) a small amount of CCl.sub.4 or CBr.sub.4 gas, includes forming a recess on an N type GaAs substrate by using a non-planar growth, performing a growth method of a P type epitaxial layer on the N type GaAs substrate by a metalorganic chemical vapor deposition method, and forming a horizontal direction PN junction array of P-GaAs/N-GaAs or P-AlGaAs/N-GaAs by introducing a gas comprising CCl.sub.4 or CBr.sub.4 .

Abstract: A fabrication method for a high output quantum wire array laser diode structure having a low threshold current and a high output is formed by fabricating a short period GaAs quantum wire array and removing an unnecessary quantum well layer with laser holographic lithography techniques and a metalorganic chemical vapor deposition and by forming a current blocking layer which is required in fabricating a laser diode with lithography techniques using a photoresist mask on a micro-patterned structure.