Semiconductor humidity sensor

Abstract

Abstract PURPOSE:To increase the output voltage and to improve the S/N ratio by adhering a humidity sensing body between a diaphragm part formed by etching a semiconductor pellet and a side wall part and deforming the diaphragm by volume variation with humidity. CONSTITUTION:The semiconductor pellet 1 is etched to provide the diaphragm 2 and piezoelectric resistance bodies 3 - 6 are formed on its surface. Then a liquid high polymer humidity sensing body 7 is dripped by a constant amount on the reverse surface of the diaphragm 2. Here, the humidity sensing body 7 expands or contracts with ambient temperature to vary in volume. At this time, the humidity sensing body 7 is adhered sufficiently even to the side wall 8 of the diaphragm 2 and the sensing part of the diaphragm 2 is drawn or pressed by the humidity sensing body 7 about the side wall 8, so that the diaphragm 2 deforms large by receiving large vertical stress on its surface. Consequently, resistance variation becomes large in the areas of the piezoelectric resistance bodies 3 - 6 and large output variation is obtained.

Inventors

• 👤 Yoshio Miyai
• 👤 宮井　良雄
• 👤 Sadao Sakamoto
• 👤 阪本　貞夫
• 👤 Yasuhiro Takeda
• 👤 安弘 武田

Bibliographic Details