| 摘要 |
<p>A mask of photo-lacquer is first deposited on the glass passivation layer, over the aluminium metallising on the substrate containing a large numbe of semiconductor conponents, exposing selected areas of the glass. The glass is then etched away in two stages in the first of which the aq. soln is used and leaving a residual thickness of glass of esp. 8000 A so that the second stage using the organic soln. does not last long enough for the organic solvent to attack the photo-lacquer significantly. The photo-lacquer used has a viscosity of 18-20 cP. Splitting the etching into two stages has the effect of preventing the aluminium metallising from being damaged by water, dissolved impurities, or by the ammonium fluoride used as buffer.</p> |
