Nature Materials 5, 893–900 (2006)

The above article contained two typographical errors:

1. In the caption for Figure 4c,d, the TFT device source–drain length should have read 50 μm (L).

2. In Methods, in the equation in the Characterization Methodology section, the parameter Nt should have been squared, that is:

The erroneous length and equation were not used in deriving any of the reported physical parameters, and the scientific conclusions of the paper remain unchanged.