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Shadow projection mask for ion implantation and ion beam lithography

  • US 4,448,865 A
  • Filed: 10/12/1982
  • Issued: 05/15/1984
  • Est. Priority Date: 10/30/1981
  • Status: Expired due to Term
First Claim
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1. A projection mask comprising;

  • a thin P+ -doped silicon layer having through holes adapted to the mask pattern, a grid supporting said silicon layer in areas where holes are not present, said grid comprising silicon ribs doped differently from the silicon layer and having on at least an upper side facing away from the grid an ion-absorbing layer, said grid on at least the surface exposed to ion radiation being electrically and thermally conductive, said silicon layer and said grid defining a silicon frame, a coating disposed on said frame where it is to be exposed to the ion beams having at least such a thickness, taking into consideration the ion energy and the characteristics of the covering material, preventing ion penetration into the silicon, said mask surface exposed to the ion radiation comprising a material resistant to the ion attack, and said silicon frame coating not causing mask deformation due to temperature and/or inherent tensions of the coating.

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