Method of manufacturing sensor having membrane structure

A method of manufacturing a sensor having a membrane structure that includes a first insulating layer, a second insulating layer, and metal stripes disposed between the first insulating layer and the second insulating layer, the metal stripes being composed of two kinds of metals, the method comprising:

• forming a metal layer composed of a first metal layer and a second metal layer, the first metal layer being formed in contact with the first insulating layer and the second metal layer being formed on the first metal layer;
• heat-treating the metal layer to enlarge a metal grain size in the metal layer;
• etching the metal layer to form the metal stripes, so that the first and the second metal layers are etched at a substantially equal etching rate;
• and
• forming the second insulating layer to cover the metal stripes.