Holder of electroconductive contactor, and method for producing the same

A method for making a holder for an electroconductive contact unit for axially slidably guiding an electroconductive needle member into and out of the holder, the electroconductive needle member including a head portion adapted to contact an object, and an enlarged diameter portion coaxially provided in the head portion, and having a larger diameter than the head portion, a compression coil spring being received in the holder for resiliently urging the enlarged diameter portion in a direction to allow the head portion to project out of the holder, characterized by the steps of:

• preparing a silicon wafer having a laminated structure including a first silicon layer, second silicon layer and silicon oxide film which is disposed between the two silicon layers;
• forming a small hole in the first silicon layer for coaxially and slidably guiding the head portion, and a large hole in the second silicon layer for receiving the enlarged diameter portion and the compression coil spring;
• forming a communication hole coaxial with the small hole and having a same diameter as the small hole in the silicon oxide film;
• and
• forming an insulating film over the inner circumferential surface of the large hole and small hole.