Doping-Free Fabrication of Carbon Nanotube Based Ballistic CMOS Devices and Circuits

Zhang, Zhiyong; Liang, Xuelei; Wang, Sheng; Yao, Kun; Hu, Youfan; Zhu, Y.; Chen, Qing; Zhou, Weiwei; Li, Yan; Yao, Yagang; Zhang, Jin; Peng, Lian‐Mao

doi:10.1021/nl0717107

Cited by 319 publications

(298 citation statements)

References 30 publications

Supporting

Mentioning

289

Contrasting

Unclassified

Order By: Relevance

“…The extracted Schottky barrier heights are low for Pd (hole barrier) and Sc (electron barrier) and agree well with some of the experimental results. 67,76 The crystallographic structure of the metal surface is also important with up to 0.2 eV difference in Schottky barrier height between different orientations. 77 It has been concluded that a junction where Al is bonded to the end of a CNT has a considerably higher Schottky barrier compared to a side bonded configuration.…”

Section: B Density Functional Theory Modelingmentioning

confidence: 99%

“…The best n-type CNTFETs fabricated without doping use Sc or Y as contact metals resulting in stable devices with high electron oncurrents. 76,93 In spite of the possibility of the presence of additional tunneling barriers and transport through multiple sub-bands, the on-state current has been used by Chen et al to estimate the Schottky barrier height of CNT-metal contacts for a large set of devices with different CNT diameters and metal work functions. 67 The Schottky barrier height is extracted by comparing the measured on-state currents to simulations which have the Schottky barrier height as a free parameter.…”

Section: A Measurements Of Schottky Barrier Heightsmentioning

confidence: 99%

See 1 more Smart Citation

Schottky barriers in carbon nanotube-metal contacts

Svensson

Campbell

2011

Journal of Applied Physics

175

132

View full text Add to dashboard Cite

Contact resistance between metal and carbon nanotube interconnects: Effect of work function and wettability Applied Physics Letters 95, 264103 (2009) Semiconducting carbon nanotubes (CNTs) have several properties that are advantageous for field effect transistors such as high mobility, good electrostatics due to their small diameter allowing for aggressive gate length scaling and capability to withstand high current densities. However, in spite of the exceptional performance of single transistors only a few simple circuits and logic gates using CNTs have been demonstrated so far. One of the major obstacles for large scale integration of CNTs is to reliably fabricate p-type and n-type ohmic contacts. To achieve this, the nature of Schottky barriers that often form between metals and small diameter CNTs has to be fully understood. However, since experimental techniques commonly used to study contacts to bulk materials cannot be exploited and studies often have been performed on only single or a few devices there is a large discrepancy in the Schottky barrier heights reported and also several contradicting conclusions. This paper presents a comprehensive review of both theoretical and experimental results on CNT-metal contacts. The main focus is on comparisons between theoretical predictions and experimental results and identifying what needs to be done to gain further understanding of Schottky barriers in CNT-metal contacts.

show abstract

Section: B Density Functional Theory Modelingmentioning

confidence: 99%

Section: A Measurements Of Schottky Barrier Heightsmentioning

confidence: 99%

Schottky barriers in carbon nanotube-metal contacts

Svensson

Campbell

2011

Journal of Applied Physics

175

132

View full text Add to dashboard Cite

show abstract

“…The unique atomic and electronic structures of a semiconducting CNT allow the n-type ohmic contact be made to its conductance band by suitable low work function metal such as Sc 21 or Y, 22 and p-type ohmic contact to be made to the valence band by high work function metal, such as Pd. 23 Carefully low temperature experiments have been carried out and shown that these n-and p-type contacts may inject carriers without barrier into the semiconducting CNTs with moderate diameter between 1.5-3.0 nm, and the linear ohmic feature in the corresponding I-V characteristic persists down to extremely low temperature, e.g.…”

Section: Doping-free Fabrication and Performance Of Cnt Fetsmentioning

confidence: 99%

A doping-free approach to carbon nanotube electronics and optoelectronics

Peng¹,

Zhang²,

Wang³

et al. 2012

AIP Advances

Self Cite

View full text Add to dashboard Cite

A doping-free approach to carbon nanotube electronics and optoelectronics The electronic properties of conventional semiconductor are usually controlled by doping, which introduces carriers into the semiconductor but also distortion and scattering centers to the otherwise perfect lattice, leading to increased scattering and power consumption that becomes the limiting factors for the ultimate performance of the next generation electronic devices. Among new materials that have been considered as potential replacing channel materials for silicon, carbon nanotubes (CNTs) have been extensively studied and shown to have all the remarkable electronic properties that an ideal electronic material should have, but controlled doping in CNTs has been proved to be challenging. In this article we will review a doping-free approach for constructing nanoelectronic and optoelectronic devices and integrated circuits. This technique relies on a unique property of CNTs, i.e. high quality ohmic contacts can be made to both the conduction band and valence band of a semiconducting CNT. High performance nanoelectronic and optoelectronic devices have been fabricated using CNTs with this method and performance approach to that of quantum limit. In principle high performance electronic devices and optoelectronic devices can be integrated on the same carbon nanotube with the same footing, and this opens new possibilities for electronics beyond the Moore law in the future.

show abstract

“…[101] More recently, close-to-perfect contacts to the tube's conduction band have been accomplished using scandium, rendering both p-and n-type SWCNT-FETs available. [102] The influence of the Schottky barriers can be reduced by selectively doping the contact regions, as has been realized on the basis of strong chemical charge-transfer between the tube and adsorbed molecules. [103] In close correspondence to graphene devices, a convenient method to estimate the Schottky-barrier height in a semiconduct- ing nanotube is SPCM performed under gate modulation.…”

Section: Carbon Nanotube-based Fetsmentioning

confidence: 99%

Carbon‐Based Field‐Effect Transistors for Nanoelectronics

2009

View full text Add to dashboard Cite

In this review, the suitability of the major types of carbon nanostructures as conducting channels of field‐effect transistors (FETs) is compared on the basis of the dimensionality and size of their π‐conjugated system. For each of these materials, recent progress in its synthesis, electrical and structural characterization, as well as its implementation into various gate configurations is surveyed, with emphasis laid onto nanoscale aspects of the FET design and the attainable device performance. Finally, promising future research directions, such as the integration of different carbon nanostructures into novel device architectures, are outlined.

show abstract

Doping-Free Fabrication of Carbon Nanotube Based Ballistic CMOS Devices and Circuits

Cited by 319 publications

References 30 publications

Schottky barriers in carbon nanotube-metal contacts

Schottky barriers in carbon nanotube-metal contacts

A doping-free approach to carbon nanotube electronics and optoelectronics

Carbon‐Based Field‐Effect Transistors for Nanoelectronics

Contact Info

Product

Resources

About