Abstract: Provided is a footwear last, being of a structure where its interior is hollow. The method includes steps of installing a parison for manufacturing a plastic vessel between left/right molds for manufacturing the footwear last, with the left/right molds opened; injecting a last manufacturing material into a tube of the parison; blowing air while closing the left/right molds; molding the material in a temperature of about 400 C to 70° C. and under an injection pressure of about 600 kg/cm2 to 1400 kg/cm2; and completing the last whose interior is hollow.

Abstract: A method for forming a deep trench in a semiconductor device includes: forming a hard mask over a substrate, forming a hard mask pattern over the substrate through etching the hard mask to thereby expose an upper portion of the substrate, forming a first trench through a first etching the exposed substrate using a gas containing bromide and a gas containing chloride and forming a second trench through a second etching the first trench using of a gas containing sulfur and fluorine, wherein a depth of the second trench is deeper than a depth of the first trench.

Abstract: Provided is a footwear last, being of a structure where its interior is hollow. The method includes steps of installing a parison for manufacturing a plastic vessel between left/right molds for manufacturing the footwear last, with the left/right molds opened; injecting a last manufacturing material into a tube of the parison; blowing air while closing the left/right molds; molding the material in a temperature of about 400 C to 70° C. and under an injection pressure of about 600 kg/cm2 to 1400 kg/cm2; and completing the last whose interior is hollow.

Abstract: A method for forming a deep trench in a semiconductor device includes: forming a hard mask over a substrate, forming a hard mask pattern over the substrate through etching the hard mask to thereby expose an upper portion of the substrate, forming a first trench through a first etching the exposed substrate using a gas containing bromide and a gas containing chloride and forming a second trench through a second etching the first trench using of a gas containing sulfur and fluorine, wherein a depth of the second trench is deeper than a depth of the first trench.

Abstract: The present disclosure relates to a method for forming a device isolation layer of a semiconductor device by a shallow trench isolation (STI). In the disclosed methods, after a nitride layer is removed from the silicon substrate, an amorphous silicon layer is deposited thereon and is oxidized to form an amorphous spacer at a side wall of the device isolation layer by etching the amorphous silicon layer.

Abstract: A wastewater treatment method for removing organic matter and nitrogen from wastewater. In the wastewater treatment method, an excessive amount of organic matter which prevents nitrifying bacteria from growing is removed in a leading aeration tank, and the conditions of the aeration tank are optimized using the nitrifying carrier to which a great amount of nitrifying bacteria can be attached for growth, such that the nitrifying bacteria can multiply therein. As a result, a large amount of wastewater can be treated within a short time, and it is possible to stably cope with a change in load of the organic matter of the wastewater. Thus, the wastewater treatment apparatus can be smaller, and an improvement in performance thereof can be expected. Also, the wastewater can be treated stably during the winter season when the activity of the nitrifying bacteria becomes low, so that the wastewater treatment method according to the present invention can be applied to most wastewater treatment plants, e.g.