| 摘要 |
1,203,106. Magnetically variable resistors. SIEMENS A.G. 25 Oct., 1967 [28 Oct., 1966], No. 48593/67. Heading H1K. A resistance element whose resistance value varies in accordance with the magnitude of the magnetic field applied thereto is prepared from a wafer of a semi-conductor crystalline material, containing substantially parallel conducting inclusions or having substantially parallel conducting strips disposed on its surface, by attaching the wafer to a suitable flat surface, grinding or etching the wafer to a thickness in the range of from 1 to 100 microns, detaching the wafer from the flat surface and attaching it to its operating support which may be curved or flexible. Thus the wafer may be secured to the flat surface by an adhesive which can be dissolved away at a temperature low enough not to damage the wafer by means of a suitable solvent, ground or etched to the desired thickness, released by means of the solvent, washed away thereby on to a cloth and thence secured by a further layer of adhesive to its final support such as a flexible film (which may for example carry a printed circuit) or the polepiece of a magnet the surface of which may be either plane or curved. Suitable semi-conductor materials are silicon, germanium or A m B v compounds such as indium antimonide and indium phosphide; in the case of indium antimonide the conducting inclusions may be constituted by needles of nickel antimonide. The wafer is preferably reduced in thickness to betweeen 5 and 50 microns and more especially to less than 20 microns before attachment to the final support; accordingly the air-gap in the magnetic field in which the device is inserted may be made very narrow whereby the magnitude of the magnetic field may be correspondingly large. |
