Controlled layer growth of WS₂ grains by chemical vapor deposition

We produced single, bi and few layered WS₂ single crystals by controlled growth condition. The single step growth with better controllability allows the fine tuning of layer number and crystal quality which has been confirmed by AFM, Raman and PL spectroscopies. Moreover, the calculated field effect mobilities based on layer number and demonstration of high performance phototransistor with prominent photoresponse facilitate the practical application of our growth recipe to other TMDs.