Abstract: Disclosed are an etching composition for selectively etching a silicon nitride, an etching method using the same, and a manufacturing method of a semiconductor device. The disclosed etching composition is an etching composition capable of increasing an etching selectivity for a silicon nitride over a silicon oxide and a polycrystalline silicon, and may include an inorganic acid, a solvent, and an additive, and the additive may include one or both of a compound containing an epoxy group and a compound containing a vinyl group. The compound containing the epoxy group may include one or more of glycid, allyl glycidyl ether, epichlorohydrin, 1,2-epoxy-3-phenoxypropane and 2,3-epoxypropyl benzene. The compound containing the vinyl group may include one or both of vinyl bromide and phenyl vinyl ether.

Abstract: The present invention provides a reflective member (10) for emitting a diffused second reflected light (63) in a second direction different from a first direction, if an incident light (61) is incident in the first direction, and for emitting a concentrated second reflected light (73) in the first direction, if an incident light (71) is incident in the second direction, the reflective member comprising: a reflective profile surface (13) for reflecting the incident light; and a first reflective surface (14) and a second reflective surface (15) provided in an alternating manner on the reflective profile surface (13) along the lengthwise direction thereof. The reflective member (10) may further comprise a film member (11) having a first surface having the reflective profile surface (13), and a second surface facing the first surface.

Abstract: A method of manufacturing a semiconductor device may include sequentially forming a tunnel insulating layer, a first conductive layer, a dielectric layer, and a second conductive layer over a semiconductor substrate, forming hard mask patterns on the second conductive layer, forming a passivation layer on surfaces of the hard mask patterns, and etching the second conductive layer, the dielectric layer, and the first conductive layer using the hard mask patterns and the passivation layer as an etch mask.