Procedure for Fabricating Electron Beam Lithography Alignment Marks
Original Publication Date: 1978-May-01
Included in the Prior Art Database: 2005-Feb-21
In alignment sensing in electron-beam photolithography wherein topographic discontinuity is used to cause electron-beam scattering, an improvement can be achieved by using a high atomic mass material for the topographic discontinuity alignment mark and the use of evaporative layers sufficiently to be lifted off. Examples of the high atomic mass elements are W(5)Si(2), WSi(2), MO(5)Si(2), MOSi(2), TaSi(2), HfSi and HfSi(2). These materials will oxidize in processing without loss of the heavy metal. The materials may be evaporated from two sources through a mask in a thickness so that the deposit may be lifted off, when desired, in processing.