Abstract: Provided are a silicon nitride film etching composition, a method of etching a silicon nitride film using the same, and a manufacturing method of a semiconductor device. Specifically, a silicon nitride film may be highly selectively etched as compared with a silicon oxide film, and when the composition is applied to an etching process at a high temperature and a semiconductor manufacturing process, not only no precipitate occurs but also anomalous growth in which the thickness of the silicon oxide film is rather increased does not occur, thereby minimizing defects and reliability reduction.

Abstract: Provided are a silicon nitride film etching composition, a method of etching a silicon nitride film using the same, and a manufacturing method of a semiconductor device. Specifically, a silicon nitride film may be stably etched with a high selection ratio relative to a silicon oxide film, and when the composition is applied to an etching process at a high temperature and a semiconductor manufacturing process, not only no precipitate occurs but also anomalous growth in which the thickness of the silicon oxide film is rather increased does not occur, thereby minimizing defects and reliability reduction.

Abstract: An inventive method for manufacturing an array of M.times.N thin film actuatable mirrors, the method being capable of preserving the structural integrity thereof, comprises the steps of: preparing an active matrix; depositing a passivation layer and an etchant stopping layer, successively, on top of the active matrix; forming a thin film sacrificial layer; depositing a first mask layer made of a silicon oxide; forming a second mask layer; forming an array of M.times.N pair of cavities, one of the cavities in each pair exposing a portion of one of the connecting terminals; removing the first and the second mask layer; forming an array of M.times.N actuating structures; removing the thin film sacrificial layer to thereby form the array of M.times.N thin film actuatable mirrors. During the formation of the cavities, the cavities is formed into a trapezoidal shape as a result of the difference in the etching rate between the first mask layer and the thin film sacrificial layer.