Up-scaling of the manufacturing of all-inkjet-printed organic thin-film transistors: Device performance and manufacturing yield of transistor arrays

All-inkjet-printed thin-film transistors (TFTs) have been demonstrated in literature using mainly laboratory inkjet equipment, simple one-channel layout and only a low number of manufactured TFT devices. We report on the development and the up-scaling of the manufacturing of all-inkjet-printed TFT arrays using industrial inkjet equipment. The manufacturing of the TFTs was carried out in ambient condition without the need for cleanroom environments or inert atmospheres and at a maximum temperature of 150 degrees C enabling the use of flexible polymer films as substrate. Arrays of 924 TFTs were manufactured on an area of about DIN A4 (297 x 420 mm(2)). This allows the consideration of statistics, e.g. to determine the process yield as a function of device design and layout. We present process yields for all-inkjet-printed TTFs up to 82% demonstrating the potential of the developed all-inkjet-printing process.