The isolation and scale-up of electronically monodisperse carbon nanotubes (CNTs) have heightened expectations for CNT-based thin-film electronic devices [1-4] and circuits [5-10]. Indeed, significant progress has been reported for individual CNT thin-film transistors (TFTs), ultimately leading to the demonstration of highly integrated CMOS circuits [11] including static random access memory (SRAM) [12]. While the latter demonstration was realized through careful development of encapsulation schemes that suppress oxygen diffusion, the underlying n-type dopants (i.e., benzyl viologen) possess intrinsic limitations that ultimately degrade electronic performance and limit circuit architecture design. This talk will address this stability and reliability issue by introducing alternative organorhodium n-type dopants for CNT TFTs.  In addition to providing controlled n-type doping as determined by TFT and Hall effect measurements, this doping scheme is compatible with top-gated CNT TFT designs. The implications of this work for very-large-scale integration (VLSI) will be discussed.

[1] D. Jariwala, V. K. Sangwan, L. J. Lauhon, T. J. Marks, and M. C. Hersam, “Carbon nanomaterials for electronics, optoelectronics, photovoltaics, and sensing,” Chem. Soc. Rev., 42, 2824 (2013).

[2] V. K. Sangwan, R. P. Ortiz, J. M. P. Alaboson, J. D. Emery, M. J. Bedzyk, L. J. Lauhon, T. J. Marks, and M. C. Hersam, “Fundamental performance limits of carbon nanotube thin-film transistors achieved using hybrid molecular dielectrics,” ACS Nano, 6, 7480 (2012).

[3] M. Engel, M. Steiner, J.-W. T. Seo, M. C. Hersam, and P. Avouris, “Hot spot dynamics in carbon nanotube array devices,” Nano Lett., 15, 2127 (2015).

[4] S. Jang, B. Kim, M. L. Geier, M. C. Hersam, and A. Dodabalapur, “Short channel field-effect-transistors with inkjet-printed semiconducting carbon nanotubes,” Small, 11, 5505 (2015).

[5] M. Ha, J.-W. T. Seo, P. L. Prabhumirashi, W. Zhang, M. L. Geier, M. J. Renn, C. H. Kim, M. C. Hersam, and C. D. Frisbie, “Aerosol jet printed, low voltage, electrolyte-gated carbon nanotube ring oscillators with sub-5 µs stage delays,” Nano Lett., 13, 954 (2013).

[6] B. Kim, S. Jang, M. L. Geier, P. L. Prabhumirashi, M. C. Hersam, and A. Dodabalapur, “High-speed, inkjet-printed carbon nanotube/zinc tin oxide hybrid complementary ring oscillators,” Nano Lett., 14, 3683 (2014).

[7] B. Kim, S. Jang, M. L. Geier, P. L. Prabhumirashi, M. C. Hersam, and A. Dodabalapur, “Inkjet printed ambipolar transistors and inverters based on carbon nanotube/zinc tin oxide heterostructures,” Appl. Phys. Lett., 104, 062101 (2014).

[8] B. Kim, M. L. Geier, M. C. Hersam, and A. Dodabalapur, “Complementary D flip-flops based on inkjet printed single-walled carbon nanotubes and zinc tin oxide,” IEEE Electron Device Lett., 35, 1245 (2014).

[9] D. Jariwala, V. K. Sangwan, J.-W. T. Seo, W. Xu, J. Smith, C. H. Kim, L. J. Lauhon, T. J. Marks, and M. C. Hersam, “Large-area, low-voltage, antiambipolar heterojunctions from solution-processed semiconductors,” Nano Lett., 15, 416 (2015).

[10] B. Kim, J. Park, M. L. Geier, M. C. Hersam, and A. Dodabalapur, “Voltage-controlled ring oscillators based on inkjet printed carbon nanotubes and zinc tin oxide,” ACS Appl. Mater. Interfaces, 7, 12009 (2015).

[11] M. L. Geier, P. L. Prabhumirashi, J. J. McMorrow, W. Xu, J.-W. T. Seo, K. Everaerts, C. H. Kim, T. J. Marks, and M. C. Hersam, “Subnanowatt carbon nanotube complementary logic enabled by threshold voltage control,” Nano Lett., 13, 4810 (2013).

[12] M. L. Geier, J. J. McMorrow, W. Xu, J. Zhu, C. H. Kim, T. J. Marks, and M. C. Hersam, “Solution-processed carbon nanotube thin-film complementary static random access memory,” Nature Nanotechnology, 10, 944 (2015).