Moisture detector

Abstract

Abstract PURPOSE:To obtain a highly sensitive moisture detector which can convert the stretching force of a moisture-sensitive body stably though it is contaminated, by joining such a moisture-sensitive body as being stretchable according to moisture on a silicon diaphragm type pressure sensor pellet as pressure applying factor to the pellet. CONSTITUTION:A silicon diaphragm type sensor pellet 1 having a diaphragm section 3 about 20 mum thick and a circular base section 2 about 300mum thick is formed from an n-type monocrystaline silicon in such a manner that p-type piezo-electric resistance areas 4a-4d are made at the diaphragm 3 by diffusion while wiring paths 5, 5... following the areas are made by evaporation or the like. The base section 2 of the pellet 1 is adhered to a header 6 and lead pins 7, 7... provided on the header 6 and wiring circuits 5, 5... are connected together with a fine metal wire 8. A moisture- sensitive stretching body 9 about several tens-several hundreds mum made of nylon is joined on the diaphragm 3 and the pellet 1 is wrapped with a case 10 by filling the portion with a gelatinous silicon 12 except for the central space including an opening 11 and the moisture-sensitive body 9. Thus, a stable stretching force of the stretching body 9 can be converted into an electrical signal sensitively with a pellet 1 free from contamination due to atmosphere to be measured.

Inventors

• 👤 Toshihiko Nishimura
• 👤 俊彦 西村
• 👤 Sadao Sakamoto
• 👤 阪本　貞夫

Bibliographic Details