Pressure sensor

Abstract

Abstract PURPOSE: To allow measurement of absolute pressure by forming stairless diffusion area arround Si diaphragm and disposing multicrystallized Si high electric conductive layer on the area and fixing glasscap on the layer by electrostatic bonding method to form a vacuum chamber. CONSTITUTION: On a diaphragm 51 formed in the center of Si substrate 50, gage areas 52∼55 are formed by diffusion and coated with SiO 2 layer 90 and windows are formed to connect these areas to terminals 80∼88 connected to an outer signal processing circuit through metal conductive layers 61∼65 at diffusion areas 56∼60 having flat surface respectively. Then, a ring-shaped fixing portion 91 consisting of multicrystallized Si is deposited as surrounding the diaphragm 51 and the ring is electrically connected to the substrate 50 through a window 89 and a boro-silicate glass made cap 100 having a same linear-expansion-coefficient with Si and a holed bottom is mounted on the ring. Between the cap 100 and the fixing portion 91, an electrostatic voltage is applied in making the portion 91 as positive electric potential to fix them respectively without adhesive agent. COPYRIGHT: (C)1980,JPO&Japio

Inventors

• 👤 Kazuji Yamada
• 👤 Kiyomitsu Suzuki
• 👤 Motohisa Nishihara
• 👤 Hiroji Kawakami
• 👤 Hideo Sato
• 👤 Shigeyuki Kobori
• 👤 Ryosaku Kanzawa
• 👤 Minoru Takahashi
• 👤 Hitoshi Minorikawa

Bibliographic Details