When a gettering sink is removed by using alkaline solution of etchant having a high selectivity to the gettering sink and a barrier film functioning as an etching stopper, residue of gettering is left. However, according to the present invention, a semiconductor film that serves as a gettering sink...http://www.google.fr/patents/US20040101997?utm_source=gb-gplus-shareBrevet US20040101997 - Method for fabricating thin film transistor
