Abstract: The present invention relates to a wavelength tunable filter capable of being driven such that reflecting mirrors move more distant as well as closer by using the principle a direction of the electromagnetic forces changes depending on the direction of the current flowing perpendicular to the external magnetic field. According to the wavelength tunable filter of the present invention, when it is necessary to have the wavelength tuning range and mechanical structure similar to the conventional wavelength tunable filter driven in only one direction, it is possible to lower the maximum force needed to drive the filter to a half, and reduce a probability that a pill-in phenomenon occurs. On the other hand, it is possible to reduce a wavelength change time of the element by increasing a resonant frequency when the same wavelength tuning ranges are implemented by using the same maximum driving forces.

Abstract: Disclosed is a a method of fabricating a MEMS device by means of surface micromachining without leaving any stiction or residues by etching silicon oxide of a sacrificial layer, which is an intermediate layer between a substrate and a microstructure, rather than by etching silicon oxide of a semiconductor device. The method according to the invention includes the steps of supplying alcohol vapor bubbled with anhydrous HF, maintaining a temperature of the supplying device and a moving path of the anhydrous HF and the alcohol to be higher than a boiling point of the alcohol, performing a vapor etching by controlling a temperature and a pressure to be within the vapor region of a phase equilibrium diagram of water, and removing silicon oxide of a sacrificial layer on a lower portion of the microstructure.

Abstract: The disclosure concerns to an optical filter for use in an optical communication device such as a multiplexer and demultiplexer. The optical filter is a Fabry-Perot filter that is formed with a silicon substrate by using a silicon micromachining process and a silicon etching process. The optical filters are applied to various optical communication devices, such as multiplexer (MUX) or demultiplexer (DEMUX) In each of the optical communication devices, the optical filters are installed and integrated on the silicon substrate together with input/output optical fibers and collimating lenses, resulting in simplifying the manufacturing process thereof and, hence, in reducing the manufacturing cost thereof. Furthermore, each of the optical filters incorporates therein an actuator so as to be tunable (wavelength-selective) in the optical filtering function and to be capable of filtering more various wavelengths in a range.

Abstract: A multi-step landing micro-mirror, a method for manufacturing the same, and a multi-step landing micro-mirror array are disclosed. The multi-step landing micro-mirror comprises a trench formed in a substrate and having N-1 steps in one side wall thereof; N plates rotated in or on the trench; and 2N springs for connecting the plates to each other; wherein the N plates are composed of an outermost first plate, a second plate connected with the first plate by the spring and located in the first plate, . . . , and a N-th plate connected with a (N-1)-th plate by the spring and located in the (N-1)-th plate, wherein when voltages are applied to the N plates and the trench, respectively, the first plate is subjected to a first landing with a predetermined rotation angle on a first step of the trench due to the constant voltage, the second plate is subjected to a second landing with the predetermined rotation angle on a second step of the trench, . . .

Abstract: An active type tunable wavelength optical filter having a Fabry-Perot structure is disclosed. A tunable wavelength optical filter which comprises a lower mirror in which silicon films and oxide films are sequentially laminated in a multi-layer and the silicon film is laminated on the highest portion; an upper mirror in which silicon films and oxide films are sequentially laminated in a multi-layer and the silicon film is laminated on the highest portion and which is spaced away from the lower mirror by a predetermined distance; a connecting means for connecting and supporting the lower mirror and the upper mirror to a semiconductor substrate; and electrode pads for controlling the gap between the lower mirror and the upper mirror by an electrostatic force and the method of manufacturing the same are provided.

Abstract: A variable optical attenuator with tunable wavelength selectivity includes at least two reflectors disposed parallel to each other at a predetermined angle from an optic axis and driving units connected to said at least two reflectors for allowing the reflectors to move back and forth in a direction perpendicular or parallel to the optic axis or to revolve centering on an axis perpendicular or parallel to the optic axis. Since the variable optical attenuator of the present invention serves as a variable optical attenuator and, at the same time, as a tunable wavelength filter, problems of insertion loss and optical alignment that might be caused by separately installing a variable optical attenuator and a wavelength filter can be effectively prevented. Moreover, by implementing the variable optical attenuator and the tunable wavelength filter by using a single device, the size of a system using the optical attenuator can be reduced.

Abstract: The present invention relates to a scanning micromirror for optical communications. The scanning micromirror comprises an outer frame having an aperture therein, an inner frame located within the aperture of the outer frame and having an aperture therein, an optical reflecting means located within the aperture of the inner frame, a plurality of first torsion springs connected between an inner wall of the outer frame and an outer wall of the inner frame, for supporting the inner frame, a plurality of second torsion springs connected between the inner wall of the inner frame and the optical reflecting means, for supporting the optical reflecting means, first comb-type electrostatic actuators for applying electrostatic torque by which the inner frame is rotated about an axis of the first torsion springs, and second comb-type electrostatic actuators for applying electrostatic torque by which the optical reflecting means is rotated about an axis of the second torsion springs.

Abstract: The present invention is disclosed a microchannel array structure embedded in a silicon substrate and a fabrication method thereof. The microchannel array structure of the present invention is formed deep inside the substrate and has high-density microscopic micro-channels. Besides, going through surface micromachining, physical and chemical properties of the silicon substrate are hardly influenced by the fabrication procedures. With microchannels buried in the substrate, the top of a microchannel array structure becomes flat, minimizing the effect of step height. That way, additional devices such as passive components, micro sensors, micro actuators and electronic devices can be easily integrated onto the microchannel array structure.

Abstract: The present invention relates to a microelectrode, a microelectrode array, and a method of manufacturing the microelectrode of which temperature can be controlled. The microelectrode comprises a sealed cavity formed in a silicon substrate for thermal isolation, a microheater formed on the sealed cavity, and an electrode heated indirectly by the microheater. According to the present invention, it is possible to manufacture with CMOS process the microelectrode and the microelectrode array which have excellent electric insulation and thermal isolation between a microheater and a silicon substrate, which has a small power consumption, which has high heating and cooling speed and which has no corrosion.

Abstract: The present invention relates to a micro electro mechanical system (MEMS); and, more particularly, to a micro pump used in micro fluid transportation and control and a method for fabricating the same. The micro pump according to the present invention comprises: trenches formed in a silicon substrate in order to form a pumping region including a main pumping region and an auxiliary pumping region; channels formed on both sides of the pumping region; a flow prevention region having backward-flow preventing layers to resist a fluid flow; inlet/outlet regions formed at each of the channels which are disposed on both ends of the pumping region; an outer layer covering the trenches of the silicon substrate and opening portions of the inlet/outlet regions; and a thermal conducting layer formed on the outer layer and over the main pumping region so that a pressure of the fluid in the main pumping region is increased by the thermal conducting layer.

Abstract: The present invention is disclosed a microchannel array structure embedded in a silicon substrate and a fabrication method thereof. The microchannel array structure of the present invention is formed deep inside the substrate and has high-density microscopic micro-channels. Besides, going through surface micromachining, physical and chemical properties of the silicon substrate are hardly influenced by the fabrication procedures. With microchannels buried in the substrate, the top of a microchannel array structure becomes flat, minimizing the effect of step height. That way, additional devices such as passive components, micro sensors, micro actuators and electronic devices can be easily integrated onto the microchannel array structure.

Abstract: The present invention relates to a micro electro mechanical system (MEMS); and, more particularly, to a micro pump used in micro fluid transportation and control and a method for fabricating the same. The micro pump according to the present invention comprises: trenches formed in a silicon substrate in order to form a pumping region including a main pumping region and an auxiliary pumping region; channels formed on both sides of the pumping region; a flow prevention region having backward-flow preventing layers to resist a fluid flow; inlet/outlet regions formed at each of the channels which are disposed on both ends of the pumping region; an outer layer covering the trenches of the silicon substrate and opening portions of the inlet/outlet regions; and a thermal conducting layer formed on the outer layer and over the main pumping region so that a pressure of the fluid in the main pumping region is increased by the thermal conducting layer.

Abstract: The disclosure concerns to an optical filter for use in an optical communication device such as a multiplexer and demultiplexer. The optical filter is a Fabry-Perot filter that is formed with a silicon substrate by using a silicon micromachining process and a silicon etching process. The optical filters are applied to various optical communication devices, such as multiplexer (MUX) or demultiplexer (DEMUX) In each of the optical communication devices, the optical filters are installed and integrated on the silicon substrate together with input/output optical fibers and collimating lenses, resulting in simplifying the manufacturing process thereof and, hence, in reducing the manufacturing cost thereof. Furthermore, each of the optical filters incorporates therein an actuator so as to be tunable (wavelength-selective) in the optical filtering function and to be capable of filtering more various wavelengths in a range.

Abstract: Disclosed is a a method of fabricating a MEMS device by means of surface micromachining without leaving any stiction or residues by etching silicon oxide of a sacrificial layer, which is an intermediate layer between a substrate and a microstructure, rather than by etching silicon oxide of a semiconductor device. The method according to the invention includes the steps of supplying alcohol vapor bubbled with anhydrous HF, maintaining a temperature of the supplying device and a moving path of the anhydrous HF and the alcohol to be higher than a boiling point of the alcohol, performing a vapor etching by controlling a temperature and a pressure to be within the vapor region of a phase equilibrium diagram of water, and removing silicon oxide of a sacrificial layer on a lower portion of the microstructure.

Abstract: A method for forming a micro cavity is disclosed. In the method for forming the cavity, a first layer is formed on a silicon layer and a trench is formed in the silicon layer by selectively etching the silicon layer. A second and a third layers are formed on the trench and on the silicon layer. Etching holes are formed through the third layer by partially etching the third layer. A cavity is formed between the silicon layer and the third layer after the second layer is removed through the etching holes. Therefore, the cavity having a large size can be easily formed and sealed in the silicon layer by utilizing the volume expansion of the silicon or the poly silicon layer. Also, a vacuum micro cavity can be formed according as a low vacuum CVD oxide layer or a nitride layer formed on the etching holes which are partially opened after the thermal oxidation process by controlling the size of the etching holes concerning the other portion of the poly silicon layer.

Abstract: A fine inductor having a 3-dimensional coil structure is disclosed. The inductor includes an insulating layer having a groove, a plurality of first conductive patterns wherein the respective first conductive patterns cover bottom and both walls of the groove formed in the insulating layer, both ends of the respective first conductive patterns are extended over upper surface of both sides of the groove, and each of the first conductive patterns is disposed at a predetermined space between adjacent first conductive patterns, and a plurality of second conductive patterns wherein one ends of the respective second conductive patterns are connected to the one ends of the first conductive patterns extended over upper surface and the other ends of the respective second conductive patterns are connected to the other ends of the adjacent first conductive patterns extended over upper surface, thereby forming a coil structure together with the first conductive patterns.

Abstract: Provided is a method of fabricating a vacuum micro-structure, which is used for an element operating in a vacuum, the method comprising the steps of: (1) entirely etching an epitaxial layer of a silicon substrate having an SOI structure including an upper silicon epitaxial layer, an interlevel insulating layer and a lower silicon bulk layer to form two electrode structures and a floating vibratory structure, and encapsulating them with a vacuum sealing substrate in a vacuum; and (2) etching the silicon substrate having the SOI stricture from the back side to the interlevel insulating layer to open the electrode structures, and forming a metal electrode.

Abstract: This invention discloses a programmable mask for exposure apparatus which is formed by an integrated pixels of a micro-devices which shut or open a light by an electrical signal. This invention provides a photolithography method by projecting on a silicon wafer a directly designed circuit pattern which is made on a programmable mask fabricated by an integration of many a micro optical shutter devices as a pixels.