Patent ID: 8486843

Claim:
A method of forming a nanoscale three-dimensional pattern in a porous semiconductor, the method comprising: depositing a continuous metal layer on a film comprising a semiconductor material; patterning the continuous metal layer to define a two-dimensional nanoscale metal pattern on the film, the two-dimensional nanoscale metal pattern including one or more features each havinq at least one lateral dimension of about 100 nm or less in size; removing semiconductor material from below the two-dimensional nanoscale metal pattern to create only substantially vertical trenches in the film, the substantially vertical trenches having a depth-to-width aspect ratio of at least about 10:1, thereby transferring the two-dimensional nanoscale metal pattern into the film to form a nanoscale three-dimensional pattern; and while removing the semiconductor material from below the two-dimensional nanoscale metal pattern, forming pores in remaining portions of the film adjacent to the substantially vertical trenches to create a porous film, thereby forming the nanoscale three-dimensional pattern in a porous semiconductor.