semiconductor micro - and nanotubes allow the incorporation of ordered structures such as quantum wells and quantum dots into them providing the potential for ultralow threshold micro - and nanoscale lasers for use in applications such as future ultrahigh - speed photonic systems as well as quantum information processing . according to the invention a means of manufacturing these with high reproducibility , low processing complexity , and at high densities is provided . also provided is a means of releasing these micro - and nanotubes with low stress and a method of “ pick - and - place ” allowing micro - and nanotubes to be exploited in devices integrated on substrates that are either incompatible with the manufacturing technique or where the area of substrate required to manufacture them is detrimental to the cost or performance of the circuit .