Method of making a Hall effect device
AssigneeInternational Standard Electric Corporation
InventorsGillies D. Pitt, Peter D. Greene, Edward J. Thrush, David H. Whysall
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Abstract
A Hall effect device comprises a thin substrate free epitaxially grown semiconductor body mounted in a magnetically permeable, e.g. ferrite, housing. The layer, which is preferably gallium arsenide or gallium indium arsenide, is grown on a substrate which, after device processing is complete, is removed by a selective etching process. In view of the relatively high sensitivity and good noise characteristics such a device with its flux concentrator is small, since the flux concentrators are themselves much smaller than with conventional Hall effect systems. Other semiconductor materials from which the novel thin Hall effect devices can be made include silicon.
Claims14
A method of making an improved Hall-effect device assembly comprising:
- providing a substrate with an epitaxial layer, having Hall electrodes thereon, and an intervening barrier layer between said substrate and said epitaxial layer, wherein said barrier layer has a composition different from said epitaxial layer and said substrate;
- removing said substrate to form a Hall-effect device by dissolving said substrate with an etchant, wherein said etchant and said barrier layer are substantially non-reactive;
- mounting said Hall-effect device in a space provided by disposing the substantially planar ends of two flux concentrator rods in substantially parallel facing relationship;
- attaching leads in conducting relationship with said Hall-electrodes;
- and
- encapsulating said Hall-effect device and said ends of said rods in a body of potting compound with said Hall-effect device disposed in said space substantially parallel to said rod ends and said leads extending externally of said body of potting compound.
Dependencies are inferred from the claim text.