Fluidic masking apparatus for etching
Abstract
Abstract IN MAKING TARGET FOR A TELEVISION CAMERA TUBE, IT IS NECESSARY TO THIN THE BACKSIDE OF A SEMICONDUCTIVE SUBSTRATE, WHICH IS OPPOSITE A FACE HAVNG A DIODE ARRAY THEREON. TO THIN THE SUBSTRATE, IT IS POSITIONED FACE DOWN ON A FLUID NONDELETERIOUS TO THE SUBSTRATE AND DIODE ARRAY. THE FLUID IS CONTAINED IN A CAVITY OF A HOLDING DEVICE. THE POSITIONING IS SUCH THAT THERE IS NO SPACE BETWEEN THE FLUID AND THE SUBSTRATE. AN APERTURED TOP MEMBER IS THEN MOUNTED ON THE SUBSTRATE AND THE FOLDING DEVICE TO RETAIN THE SUBSTRATE ON THE FLUID. THE ASSEMBLY OF THE HOLDING DEVICE AND TOP MEMBER WITH THE SUBSTRATE THEREBETWEEN IS IMMERSED AND ROTATED IN AN ETCHANT TO THIN THE BACKSIDE OF THE SUBSTRATE THROUGH THE APERTURE OF THE TOP MEMBER. THE FLUID PROVIDES A TIGHT SEAL ON THE FACE OF THE SUBSTRATE TO PREVENT THE ETCHANT FROM DAMAGING SUCH FACE AND THE DIODE ARRAY THEREON. A VENT EXTENDING FROM THE CAVITY OF THE HOLDING DEVICE TO ITS OUTER EDGE ASSISTS IN THE SUBSEQUENT REMOVAL OF THE SUBSTRATE FROM THE CAVITY.
Inventors
- 👤 Harold Arthur Hetrich
Bibliographic Details
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