Patent ID: 7432514

Claim:
A method of controlling a beam used to generate a pattern on a target surface, comprising: generating a beam of charged particles and directing said beam to a mask surface; and causing said beam to be one of absorbed by and reflected from said mask surface, thereby either precluding or allowing said beam to strike said target surface based on a reflection characteristic of said mask surface, wherein said reflection characteristic is due to a mechanism such that a pattern on said mask surface is changeable without having to re-fabricate said mask, wherein said mechanism is due to providing a difference of electrical potential on said mask surface and said difference of electrical potential is changeable without further modifying said mask, thereby providing a programmable mask by selectively controlling an electrical potential on different portions of said mask surface to change a pattern thereon, wherein said programmable mask comprises a matrix of programmable portions on said mask surface, and wherein said matrix of programmable portions comprises a matrix of photodiodes.