Browse Prior Art Database

High-Sensitivity Magnetosensitive Microdevice

IP.com Disclosure Number: IPCOM000060014D
Original Publication Date: 1986-Feb-01
Included in the Prior Art Database: 2005-Mar-08
Document File: 2 page(s) / 46K

Publishing Venue

IBM

Related People

Greschner, J: AUTHOR [+2]

Abstract

The magnetosensitive microdevice is realized as an integrated solidstate sensor. In addition to being utilized for sensing, the semiconductor material of the sensor, say, silicon, serves to provide electronic functions, such as signal amplification, multiplexing, digitalization, immediately adjacent to the sensor. Fig. 4 is a sectional view of the device. The sensor comprises a P+N-N+ diode 3, 2',4 realized as an about 1 to 2 mm thick self-supporting membrane 2. Magnetic induction B, provided in the plane of membrane 2 at the front side of the sensor vertically to a current I, reaching the diode through wiring 7, 8 and contacts, connected to a voltage V, causes injected electrons and holes to be deflected in diode N- zone 2'.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 52% of the total text.

Page 1 of 2

High-Sensitivity Magnetosensitive Microdevice

The magnetosensitive microdevice is realized as an integrated solidstate sensor. In addition to being utilized for sensing, the semiconductor material of the sensor, say, silicon, serves to provide electronic functions, such as signal amplification, multiplexing, digitalization, immediately adjacent to the sensor. Fig. 4 is a sectional view of the device. The sensor comprises a P+N-N+ diode 3, 2',4 realized as an about 1 to 2 mm thick self-supporting membrane 2. Magnetic induction B, provided in the plane of membrane 2 at the front side of the sensor vertically to a current I, reaching the diode through wiring 7, 8 and contacts, connected to a voltage V, causes injected electrons and holes to be deflected in diode N- zone 2'. Deflection is effected to the silicon/ion-implanted damage zone 9 interfaced with a high recombination rate at the front side or to the silicon/SiO2 layer 10 interfaced with a low recombination rate at the back side. This increases or decreases the medium carrier density and thus the current through diode 3, 2',4, depending on the direction of induction B sensed at the front side of the device. Figs. 1 to 4 show the manufacturing process of the sensor. A P- doped silicon wafer 1 is used as base material. By inversion doping or homoepitaxy, a 1 to 2 mm thick N- silicon layer 2' is applied to the front side. Then P+ and N+ regions 3 and 4, respectively, are implanted (Fig. 1), and the wafer is thin-etched through a rear window lithographically defined by SiO2 sputtering (not shown). Sputtered SiO2 is also used to protect the front side of the wafer. The wet etch step, used to form membrane 2, is carried out with a mixture of ethylene diamine, pyrocatechol and water, applying an etch stop potential to the PN junction. After wet etching, the p...