Abstract:
A contact hole forming method and a method of manufacturing semiconductor device using the same may include forming a layer on a substrate; anisotropically etching the layer to form a dummy contact hole exposing the substrate; isotropically etching a sidewall of the dummy contact hole to form a contact hole by alternatively and repeatedly supplying an etching solution including a fluoride salt in a low-polarity organic solvent and deionized water to the dummy contact hole. The methods increase reliability of semiconductor memory devices.
Abstract:
A cylinder cushion device is provided for a hydraulic cylinder of an excavator, to prevent a piston from colliding with an end boss and absorb shock due to collision. Pressure higher than design strength of the hydraulic cylinder does not occur even if external force is given to the hydraulic cylinder. The cylinder cushion device includes a tube constituting a receiving chamber of hydraulic oil, a rod performing straight line motion, a piston fixed onto the rod and dividing the receiving chamber of the tube, an end boss, a cushion sleeve provided on the rod to be adjacent to the piston, for generating a predetermined cushion pressure inside the rod-side chamber if the piston is adjacent to the end boss during straight line motion of the rod, and an elastic body provided on the cushion sleeve for preventing the piston from colliding with the end boss and absorbing shock by means of its elasticity.
Abstract:
Disclosed are a composition for removing photoresist, a method of removing photoresist and a method of manufacturing a semiconductor device using a composition. The composition may include a ketone compound and a first polar aprotic solvent. The composition may also include the ketone compound and a second polar aprotic solvent. Moreover, the composition may include the first polar aprotic solvent and a second polar aprotic solvent with or without the ketone compound. The first polar aprotic solvent has at least one of an ether compound and an ester compound, and the second polar aprotic solvent has at least one of a sulfur-containing compound and a nitrogen-containing compound.
Abstract:
A hydraulic circuit for heavy construction equipment to reduce a speed of a swing apparatus while a working apparatus such as a boom is concurrently operated has a work control valve which controls a working apparatus cylinder; a confluence valve which combines a hydraulic fluid of the second hydraulic pump with the work unit flow path based on a positions switch; a swing control valve which controls the hydraulic swing motor; and a disconnection valve which disconnects the hydraulic fluid supplied to at least one of the swing motors.
Abstract:
In a composition for etching silicon oxide, and a method of forming a contact hole using the composition, the composition which includes from about 0.01 to about 2 percent by weight of ammonium bifluoride, from about 2 to about 35 percent by weight of an organic acid, from about 0.05 to about 1 percent by weight of an inorganic acid, and a remainder of a low polar organic solvent. The composition may reduce damages to a metal silicide pattern that may be exposed in an etching process performed for forming the contact hole.
Abstract:
Disclosed are a composition for removing photoresist, a method of removing photoresist and a method of manufacturing a semiconductor device using a composition. The composition may include a ketone compound and a first polar aprotic solvent. The composition may also include the ketone compound and a second polar aprotic solvent. Moreover, the composition may include the first polar aprotic solvent and a second polar aprotic solvent with or without the ketone compound. The first polar aprotic solvent has at least one of an ether compound and an ester compound, and the second polar aprotic solvent has at least one of a sulfur-containing compound and a nitrogen-containing compound.
Abstract:
A fabrication method of a semiconductor device is disclosed. Particularly, in the process of forming a gate oxide film on a semiconductor substrate, the method for forming a gate oxide film of a semiconductor device comprises the steps of first-annealing the semiconductor substrate in a nitrogen (N.sub.2) atmosphere; forming a gate oxide film by wet-oxidizing the annealed semiconductor substrate at a low temperature in a mixed gas atmosphere of oxygen (O.sub.2) and hydrogen (H.sub.2); and second-annealing the semiconductor substrate where gate oxide film has been formed, at a high temperature in a nitrogen (N.sub.2) atmosphere. Accordingly, the thinning phenomenon of the gate oxide film near the field oxide film is prevented and the instability such V.sub.FB in the conventional field oxidation method is considerably recovered. Also, the field concentration phenomenon is decreased and tolerance to dielectric breakdown is increased.
Abstract:
A hydraulic circuit for an excavator is provided, which includes first to third hydraulic pumps, a first traveling control valve and a first boom control valve successively installed along a first center bypass line from a downstream side of the first hydraulic pump, a second traveling control valve and a second boom control valve successively installed along a second center bypass line from a downstream side of the second hydraulic pump, a swing control valve connected between the third hydraulic pump and a swing motor to control the operation of the swing motor in accordance with an external valve switching signal, and a confluence line connected between a third center bypass line and a flow path of the second boom control valve to make hydraulic fluid from the third hydraulic pump join hydraulic fluid in a neutral position of the swing control valve. According to the hydraulic control circuit, the swing motor can be controlled independently by the fluid pressure being applied through the third hydraulic pump, and the speed of actuators can be kept without insufficiency of the flow rate during the swing composite operation through joining of the hydraulic fluid from the hydraulic pump and the hydraulic fluid from the working devices such as the boom, arm, and the like.
Abstract:
Provided is an apparatus and method for analyzing contaminants on a wafer. The apparatus includes: a wafer holder for supporting a wafer on which contaminants to be analyzed are located, a laser ablation device for irradiating a laser to the wafer to extract a discrete specimen from the wafer, an analysis cell for collecting a discrete specimen from the surface of the wafer by irradiating the laser, and an analysis device connected to the analysis cell for analyzing contaminants from the collected discrete specimen.
Abstract:
Provided herein are metal detection reagents including at least one ammonium salt of Formula 1: wherein R1, R2, R3 and R4 are independently selected from the group consisting of hydrogen, C1-30 alkyl and C3-14 aryl, and X− is independently selected from the group consisting of bromide, chloride, iodide, fluoride, nitrate, phosphate and sulfate and methods of using the metal detection reagents to monitor one or more metal ion levels in a solution.