Kim Bongjun, Park Jaeyoung, Geier Michael L, Hersam Mark C, Dodabalapur Ananth
†Microelectronics Research Center, The University of Texas at Austin, Austin, Texas 78758, United States.
‡Department of Electrical and Computer Engineering, The University of Texas at Austin, Austin, Texas 78712, United States.
ACS Appl Mater Interfaces. 2015 Jun 10;7(22):12009-14. doi: 10.1021/acsami.5b02093. Epub 2015 May 27.
A voltage-controlled ring oscillator is implemented with double-gate complementary transistors where both the n- and p-channel semiconductors are deposited by inkjet printing. Top gates added to transistors in conventional ring oscillator circuits control not only threshold voltages of the constituent transistors but also the oscillation frequencies of the ring oscillators. The oscillation frequency increases or decreases linearly with applied top gate potential. The field-effect transistor materials system that yields such linear behavior has not been previously reported. In this work, we demonstrate details of a material system (gate insulator, p- and n-channel semiconductors) that results in very linear frequency changes with control gate potential. Our use of a double layer top dielectric consisting of a combination of solution processed P(VDF-TrFE) and Al2O3 deposited by atomic layer deposition leads to low operating voltages and near-optimal device characteristics from a circuit standpoint. Such functional blocks will enable the realization of printed voltage-controlled oscillator-based analog-to-digital converters.
一种压控环形振荡器是用双栅互补晶体管实现的，其中n沟道和p沟道半导体均通过喷墨印刷沉积。在传统环形振荡器电路中添加到晶体管的顶栅不仅控制组成晶体管的阈值电压，还控制环形振荡器的振荡频率。振荡频率随施加的顶栅电势线性增加或减小。产生这种线性行为的场效应晶体管材料系统此前尚未见报道。在这项工作中，我们展示了一种材料系统（栅极绝缘体、p沟道和n沟道半导体）的细节，该系统导致频率随控制栅极电势的变化非常线性。我们使用由溶液处理的P(VDF-TrFE)和通过原子层沉积沉积的Al2O3组成的双层顶部电介质，从电路角度来看，这会带来低工作电压和接近最佳的器件特性。这种功能块将有助于实现基于印刷压控振荡器的模数转换器。
