Abstract: Provided is a water pump having improved efficiency by simplifying its structure, the water pump including: an outer housing having a shape of a container, and including an inlet part positioned at a lower end, and an outlet part positioned at a side of an upper end; an inner housing having a shape of a container, including a communication hole positioned at an upper end and communicating the inside and outside with each other, and inserted into the outer housing; a thrust key coupled to the inside of the outer housing; and a first screw and a second screw, inserted into the inner housing, having lower ends supported by the thrust key, and engaged with each other to be rotated together.

Abstract: Provided is a water pump which may be easily manufactured and a manufacturing method thereof, the water pump including: a motor housing having a concave container shape; a lower casing including a first side wall protruding downward for a lower end of the first side wall to be in contact with an upper end of the motor housing; and an upper casing fitted to the outside of the lower casing, and including a second side wall protruding downward for a lower end of the second side wall to be in contact with the upper end of the motor housing, wherein the upper end of the motor housing, the lower end of the first side wall, and the lower end of the second side wall are simultaneously fusion-coupled with one another.

Abstract: Disclosed are a polymer for a chemically amplified resist represented as and a resist composition using the same. In the above Chemical formula 1, X represents vinyl ether derivatives or olefin derivatives, at least one of R1, R2, R3, and R4 is an alkyl group with 1 to 30 carbon atoms containing at least one functional group of a hydrogen atom, an ether group, an ester group, a carbonyl group, an acetal group, an epoxy group, a nitryl group (—CN), and an aldehyde group, l, m, n, o and p respectively represent repeating units, l represents a real number of 0.05 to 0.5, m and n respectively represent real numbers of 0.1 to 0.7, o and p respectively represent real numbers of 0 to 0.7, and a sum of l, m, n, o and p is 1.

Abstract: Disclosed are a polymer for a chemically amplified resist represented as and a resist composition using the same. In the above Chemical formula 1, X represents vinyl ether derivatives or olefin derivatives, at least one of R1, R2, R3 and R4 is an alkyl group with 1 to 30 carbon atoms containing at least one functional group of a hydrogen atom, an ether group, an ester group, a carbonyl group, an acetal group, an epoxy group, a nitryl group (—CN), and an aldehyde group, l, m, n, o and p respectively represent repeating units, l represents a real number of 0.05 to 0.5, m and n respectively represent real numbers of 0.1 to 0.7, o and p respectively represent real numbers of 0 to 0.7, and a sum of l, m, n, o and p is 1.