Arrays of silicon nanotubes; (SiNTs) with controllable architectures, wall thicknesses and crystallinity are fabricated by a new template-assisted technique. The method includes a sequence of glancing angle deposition of the templates, low-pressure CVD shell-Si coating, ion-milling to expose the templates, and wet-chemical etching for template removal. The technique may be generally adapted to a wide variety of morphologies and NT materials.