Fig. 16
Reprinted from [108], © 2000 SPIE, reproduced with permission
Schematic representation of the technique comprising of circular openings suggested by Chen et al. [108]. After etching, due to underetching at the mask edges, the corners of the square merge with each other with a just one corner merging, b odd number of corners merging c even number of corners merging. In the first case, the ⟨100⟩ direction lies between the two merged corners. In the case of odd number of merging, the precise ⟨100⟩ direction passes through the middle corner. In cases where there is even number of merges of corners, the ⟨100⟩ direction passes through the radial diagonal of the central square