Abstract: The present invention is directed to method for manufacturing a liquid crystal display apparatus in which a thin film transistor formed by successively depositing on a glass substrate a gate electrode, a gate insulating film, an active layer made of amorphous silicon, a source electrode and a drain electrode is used for driving liquid crystal. The method includes steps of: forming the gate electrode by patterning a gate metal layer coating the glass substrate by a wet etching process using an etchant containing cerium ammonium nitrate; removing an etching reaction product adhering on the substrate by washing it with a hydrofluoric acid solution; and forming the gate insulating film.