Semiconductor pressure converter

Abstract

Abstract PURPOSE: To reduce the error due to hydro static pressure, by avoiding the swelling of the bonding layer at the side circumference of the substrate through the reduced bonding area of the fixed base than the external size of the pressure converting substrate. CONSTITUTION: The diaphragm 2 thin in thickenss is formed at the center of the N type Si singlecrystal substrate 1, and it is covered with the insulation layer 4. Next, opening is placed at the diaphragm 2 and the P type resistive layres 3 1 and 3 2 are formed by diffusion and after coating the Al electrode wiring layar 5 on it, the leads 6 are bonded. The thick part at the circumference of the pressure conversion substrate 17 thus constituted is heated and fixed via the bonding layer 18 consisting of galss powder on the fixed base 19 of Si. At this time, the bonding edge surface is made smaller than the external diameter of the pressure converting substrate 17. Thus, no bonding layer 18 is swelled up on the side surface of the substrate 17, and the stress based on the difference of thermal expandion rate between the bonding layer 18 and the substrate 17 is operated from external circumferenc to the substrate 17, and the error due to hydrostatic pressure is made very small COPYRIGHT: (C)1979,JPO&Japio

Inventors

• 👤 Shunji Shiromizu
• 👤 Susumu Kimijima

Bibliographic Details