SEMICONDUCTOR PRESSURE SENSOR

• Main Authors: NAGASAKA HIROSHI, KANO HAJIME, YOKOTA TAKEO
• Format: Patent
• Language: English
• Published: 05.11.1996
• Edition: 6
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT; MEASURING; MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER,MECHANICAL EFFICIENCY, OR FLUID PRESSURE; MEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION,OR SHOCK; PHYSICS; SEMICONDUCTOR DEVICES; TESTING

PURPOSE: To improve precision in pressure measurement by a method wherein the semiconductor piezoresistant element of a pressure sensor is insulated from a peripheral insulating layer excluding the electrode part on a silicon substrate. CONSTITUTION: The pressure sensor 100 is provided with a silicon substrate 1 made of an N type single crystal silicon wafer while a diaphragm 2 made of a recession is formed on the central part of a pressure detecting surface on the lower surface side of a silicon substrate 1. The diaphragm 2 is impressed with a measuring body M through the intermediary of a pressure introducing port. Besides, an insulating layer 3 is formed on the surface side of a silicon substrate 1 while a conductor layer 5 is formed on the insulating layer 3. Another insulating layer 6 is formed on the conductor layer 5 while a semiconductor piezoresistant element 4 is provided on the insulating layer 6. A solid potential electrode 7 is connected to the conductor layer 5. Finally, a surface insulating layer 8 made of a silicon nitride film is so formed as to cover the surface of the insulating layer 6, the side face of the conductor layer 5 and the surface of the peripheral part of the insulating layer 3, the semiconductor piezoresistant element 4 and the solid potential electrode 7.