Low-voltage-operating organic complementary circuits based on pentacene and C60 transistors

Low‐Voltage Ring Oscillators Based on Polyelectrolyte‐Gated Polymer Thin‐Film Transistors

“…Moreover, the transistor has a subthreshold swing of 0.15 V per decade and a maximum transconductance per channel width of 13.5 mS mm À1 , which both are comparable to the highest values reported for OTFT circuits. [10,13,17,18] However, an on/off current ratio of 4000 is rather low in comparison. The P(VPA-AA) gate insulator (70 nm thick) has, when sandwiched between the Ti gate electrode and the semiconductor, an effective capacitance of about 3 mF cm À2 .…”

“…[8] Hence, tremendous efforts are presently devoted to reducing the driving voltage of printable OTFTs simultaneously to keeping the delay time short. Figure 1 shows the lowest reported signal delay times per stage at different supply voltages (V DD ) for p-channel, [9][10][11][12][13][14][15] n-channel, [16] and complementary [17][18][19][20] OTFT circuits (ring oscillators). The graph illustrates the difficulty of combining high-speed with low-voltage operation.…”

Organic complementary oscillators with stage-delays below 1 μs

“…4 The circuits can operate at supply-voltages ͑V DD ͒ as low as 3 V. 5 Because of the intrinsic limitations ͑e.g., static power consumption, design complexity͒ of the unipolar logic that is used in those designs, the development of organic complementary logic, in which hole-conducting p-type transistors and electron-conducting n-type transistors are integrated on one substrate, currently receives a lot of attention. [6][7][8][9] However, inverter stage-delays so far are much larger than the best reports of unipolar inverters. The main reason for this is that integration of champion n-type and p-type materials in a single process flow is challenging, and in complementary logic the slower transistor dictates the overall speed.…”

Organic complementary ring oscillators using a functional polymer interfacial layer for highly improved oscillation frequency

“…To achieve a high oscillation frequency in complementary ring oscillators, the balance of p-and n-type OFET characteristics is of great importance, but they are challenging for OFETbased ring oscillators because organic semiconductors show much inferior n-type property. To solve the problem, there have been a number of studies, such as adding an additional compensation circuit [6,7], adjusting the channel width [8], and choosing the p-type material bearing a mobility compared to the one of its counterpart n-type material [9,10]. However, because these methods encounter other challenges, such as a high processing cost, complexity to realize highly integrated circuits, and a limited material choice, therefore a novel approach is required to realize high-performance organic ring oscillators.…”