Micro-switching device and manufacturing method for the same

A method for making a micro-switching device by processing a material substrate having a laminated structure including a first layer, a second layer and an intermediate layer between the first and the second layers, the micro-switching device comprising:

• a base substrate;
• a fixing member bonded to the base substrate;
• a movable part including a stationary end fixed to the fixing member and extending along the base substrate;
• a movable contact electrode provided on the movable part at a surface facing away from the base substrate;
• a pair of stationary contact electrodes each including a region facing the movable contact electrode and each bonded to the fixing member;
• a movable driver electrode provided between the movable contact electrode and the stationary end on the movable part at a surface facing away from the base substrate;
• and a stationary driver electrode bonded to the fixing member and including an elevated portion having a region facing the movable driver electrode, where the elevated portion has a step structure provided by steps facing the movable driver electrode, the steps being closer to the base substrate as the steps are farther from the movable contact electrode;
• the method comprising the steps of:
• forming the movable contact electrode and the movable driver electrode on the first layer at a first portion to be processed into the movable part;
• forming the fixing member and the movable part by subjecting the first layer to anisotropic etching until the intermediate layer is reached, the anisotropic etching being performed via a masking pattern masking the first portion and a second portion of the first layer to be processed into the fixing member;
• forming a sacrifice film covering a first-layer side of the material substrate;
• forming recesses in the sacrifice film for forming the elevated portion of the step structure, the recesses corresponding in position to the movable driver electrode;
• making a plurality of openings in the sacrifice film for exposing regions of the fixing member to which the pair of stationary contact electrodes and the stationary driver electrode are to be bonded;
• forming the stationary driver electrode and the pair of stationary contact electrodes, the stationary driver electrode being bonded to the fixing member and including at least the elevated portion having a region facing the movable driver electrode via the sacrifice film, each of the pair of stationary contact electrodes being bonded to the fixing member and having a region facing the movable contact electrode via the sacrifice film;
• removing the sacrifice film;
• and
• removing the intermediate layer between the second layer and the movable part by etching.