A simple method for preventing oxidization of an aluminum surface of terminal electrode, increase of pressure contact resistance, unstability and reduction of connection reliability is provided. In a terminal electrode part on a reactive matrix substrate, for being connected to an external drive circuit, connecting electrodes are formed by using aluminum or an aluminum alloy, at least their surfaces connected to TCP are covered with an insulating film of aluminum oxide or consisting of a laminate film of aluminum oxide aluminum hydroxide, and the insulating film is selectively removed in a step subsequent to the final step in a cell formation process. In this way, adverse effects of the heat treatment processes such as the annealing in the array formation process and the orientation film sintering of the cell formation process and the oxidization of the connecting electrode surface in the washing.