Query: large-area integration of two

Candidate papers:

abstract: Integrating two dimensional (2D) materials into semiconductor manufacturing lines is essential to exploit their material properties in a wide range of application areas. However, current approaches are not compatible with high volume manufacturing on wafer level. Here, we report a generic methodology for large area integration of 2D materials by adhesive wafer bonding. Our approach avoids manual handling and uses equipment, processes, and materials that are readily available in large scale semiconductor manufacturing lines. We demonstrate the transfer of CVD graphene from copper foils (100 mm diameter) and molybdenum disulfide (MoS2) from SiO2/Si chips (centimeter sized) to silicon wafers (100 mm diameter) Furthermore, we stack graphene with CVD hexagonal boron nitride and MoS2 layers to heterostructures, and fabricate encapsulated field effect graphene devices, with high carrier mobilities of up to \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin} 69pt} \begin{document}$4520\\mathrm{cm}^2{\mathrm{V} 1}\mathrm{s} 1}\end{document}4520cm2V 1s 1. Thus, our approach is suited for backend of the line integration of 2D materials on top of integrated circuits, with potential to accelerate progress in electronics, photonics, and sensing.
author_names: Arne Quellmalz

Xiaojing Wang

Simon Sawallich

Burkay Uzlu

Martin Otto

Stefan Wagner

Zhenxing Wang

Maximilian Prechtl

Oliver Hartwig

Siwei Luo

Georg S Duesberg

Max Christian Lemme

Kristinn B Gylfason

Niclas Roxhed

Goran Stemme

Frank Niklaus
title: Large area integration of two dimensional materials and their heterostructures by wafer bonding
venue: Nature communications
year: 2021

abstract: We have fabricated large area integrated top gate <inline formula> <tex math notation="LaTeX"{n} /tex math>/inline formula>MISFETs with sputter deposited MoS<sub>2</sub> film having n type operation. A sputtering method enables us to form a large area MoS<sub>2</sub> thin film followed by H<sub>2</sub>S annealing to compensate sulfur vacancies. Two passivation films of ALD Al<sub>2</sub>O<sub>3</sub> enhance the process endurance of MoS<sub>2</sub> channel. Therefore, we demonstrate TiN top gate <inline formula> <tex math notation="LaTeX"{n} /tex math>/inline formula>MISFET, which is a substantial first step to realize industrial chip level LSIs with MoS<sub>2</sub> channel FETs.
author_names: Kentaro Matsuura

Jun'ichi Shimizu

Mayato Toyama

Takumi Ohashi

Iriya Muneta

Seiya Ishihara

Kuniyuki Kakushima

Kazuo Tsutsui

Atsushi Ogura

Hitoshi Wakabayashi
title: Sputter Deposited MoS2 {n} MISFETs With Top Gate and Al2O3 Passivation Under Low Thermal Budget for Large Area Integration
venue: IEEE Journal of the Electron Devices Society
year: 2018

abstract: Two dimensional transition metal chalcogenides (2D TMDCs) show photoluminescence (PL) as a result of direct band gap transitions at visible wavelengths. Although 2D TMDCs have been considered for use in next generation optoelectronics, practical applications are restricted by their low absorption and emission efficiency. To overcome these limitations using plasmonic local field enhancement, we propose the integration of gold nanoparticles with 2D TMDCs over a centimeter scale area. Using self assembled gold nanoshell monolayers, we produce a 10 fold increase in the PL of 2D TMDCs. We expect our method to provide a means for the large area, low cost fabrication of plasmon enhanced 2D TMDCs for optoelectronic applications.
author_names: Min-Gon Lee

SeokJae Yoo

Taehyung Kim

Q -Han Park
title: Large area plasmon enhanced two dimensional MoS2.
venue: Nanoscale
year: 2017

abstract: Here we present a very fast, selective mechanical approach for transferring graphene with low levels of copper contamination from seed wafers on which it was grown to target wafers for very large scale integration (VLSI) electronics. We found that graphene/copper or copper/silicon oxide delamination paths could be selected by slow and faster separation rates, respectively. Thus graphene can be transferred to a target wafer, either exposed or protected by the seed copper layer, which can later be removed by etching. Delamination paths were identified by SEM and Raman spectroscopy. The sheet resistance of the graphene produced by the two approaches was slightly higher than graphene transferred by a PMMA wet transfer process, indicating reduced impurity doping, and the variation in the sheet resistance values was much lower. Copper contamination levels, quantitatively established by TOF SIMS, were several orders of magnitude lower than the values for PMMA assisted transfer. In addition, we demonstrated that top gated transistor devices from our mechanical, delamination transferred graphene exhibited superior transistor behavior to PMMA assisted wet transfer graphene. The adhesion energy, strength and range of the interactions were quantitatively determined by nonlinear fracture analyses, and suggest that the roughness of the interface between graphene and copper plays an important role with implications for improvements in manufacturing processes.
author_names: Seung Ryul Na

Somayyeh Rahimi

L Tao

Harry Chou

Shideh K Ameri

Deji Akinwande

Kenneth M Liechti
title: Clean graphene interfaces by selective dry transfer for large area silicon integration.
venue: Nanoscale
year: 2016

abstract: MXenes, an emerging class of two dimensional (2D) transition metal carbides and nitrides, have potential for application as high performance, low cost electrodes in organic field effect transistors (OFETs) because of their water dispersibility, high conductivity, and work function tunability. In this study, we successfully fabricated a large scale, uniform Ti3C2Tx MXene electrode array on a flexible plastic substrate for application in high performance OFETs. The work function of the Ti3C2Tx MXene electrodes was also effectively modulated via chemical doping with NH3. The fabricated OFETs with Ti3C2Tx MXene electrodes exhibited excellent device performance, such as a maximum carrier mobility of ~1 cm2*V 1*s 1 and an on off current ratio of ~107 for both p type and n type OFETs, even though all the electrode and dielectric layers were fabricated on the plastic substrate by solution processing. Furthermore, MXene electrode based complementary logic circuits, such as NOT, NAND, and NOR, were fabricated via integration of p type and n type OFETs. The proposed approach is expected to expand the application range of MXenes to other OFET based electronic devices, such as organic light emitting displays and electronic skins.
author_names: Benzheng Lyu

Minjee Kim

Hongyue Jing

Joohoon Kang

Chuan Qian

Sungjoo Lee

Jeong Ho Cho
title: Large Area MXene Electrode Array for Flexible Electronics.
venue: ACS nano
year: 2019

abstract: Monolayer Transition Metal Dichalcogenides (TMDs) have recently attracted great interest in the field of photonics because of their distinctive optical and spin properties. In contrast to bulk TMD materials, which are indirect bandgap semiconductors, monolayer TMDs are highly optically active due to a direct bandgap ranging between 1 and 2 eV [1] The coupling of TMD excitons to optical fields can be dramatically enhanced by integration with nanophotonic resonators. For instance, enhanced light extraction, signatures of Purcell enhanced emission and even lasing in coupled systems of TMD monolayers transferred onto two dimensional GaP based photonic crystal cavities (PCCs) [2,3] as well as microdisk cavities [4] was reported.
author_names: Sebastian Hammer

H Moritz Mangold

Dominic Martinez-Ta

Ariana E Nguyen

Ludwig Bartels

Hubert J Krenner
title: Large area grown MoS2 and its integration in geometrically tunable photonic crystal cavities
venue: 2017 Conference on Lasers and Electro Optics Europe European Quantum Electronics Conference (CLEO/Europe EQEC)
year: 2017

abstract: Building on a unique two step, simple MBE growth technique, we have investigated possible dislocation locking mechanisms by dopant impurities, coupled with artificially introduced oxygen. In the case of n type Ge grown on Si, our materials characterization indicates that the dislocation density (DD) can reach the 10 5 cm 2 level, compared to p type and undoped Ge on Si (GoS) We note that our Ge film covers the entire underlying Si substrate at the wafer scale without mesas or limited area growth. In this presentation, we will focus on the use of n type impurity (phosphorus) diffusing from the Si substrate and the introduction of O at the Ge Si interface. The O is introduced by growing a thin chemical SiO2 layer on top of the Si substrate before Ge epitaxy begins. Z contrast cross sectional TEM images suggest the presence of oxygen precipitates in ntype Ge, whereas these precipitates appear absent in p type Ge. These oxygen precipitates are known to lock the dislocations. Supporting the argument of precipitate formation, the TEM shows fringes due to various phase boundaries that exist at the precipitate/Ge crystal interface. We speculate that the formation of phosphorus (P) segregation resulting from slow diffusion of P through precipitates at the precipitate/Gecrystal interface facilitates dislocation locking. Impurity segregations in turn suppress O
author_names: Swapnadip Ghosh
title: Large area, wafer scale epitaxial growth of germanium on silicon and integration of high performance transistors
year: 2015

abstract: Heterostructures involving two dimensional (2D) transition metal dichalcogenides and other materials such as graphene have a strong potential to be the fundamental building block of many electronic and optoelectronic applications. The integration and scalable fabrication of such heterostructures are of the essence in unleashing the potential of these materials in new technologies. For the first time, we demonstrate the growth of few layer MoS2 films on graphene via nonaqueous electrodeposition. Through methods such as scanning and transmission electron microscopy, atomic force microscopy, Raman spectroscopy, energy and wavelength dispersive X ray spectroscopies, and X ray photoelectron spectroscopy, we show that this deposition method can produce large area MoS2 films with high quality and uniformity over graphene. We reveal the potential of these heterostructures by measuring the photoinduced current through the film. These results pave the way toward developing the electrodeposition method for the large scale growth of heterostructures consisting of varying 2D materials for many applications.
author_names: Yasir J Noori

Shibin Thomas

Sami Ramadan

Danielle E Smith

Victoria K Greenacre

Nema M Abdelazim

Yisong Han

Richard Beanland

Andrew L Hector

Norbert Klein

Gillian Reid

Philip N Bartlett

C H (Kees) de Groot
title: Large Area Electrodeposition of Few Layer MoS2 on Graphene for 2D Material Heterostructures.
venue: ACS applied materials interfaces
year: 2020

abstract: Heterostructures involving transition metal dichalcogenides and other two dimensional materials such as graphene have a strong potential to be the fundamental building block of many electronic and opto electronic applications. The integration and scalable fabrication of such heterostructures is of essence in unleashing the potential of such technologies. For the first time, we demonstrate the growth of films as thin as a bilayer MoS2 on monolayer graphene via non aqueous electrodeposition. Through methods such as scanning electron microscopy, atomic force microscopy, Raman spectroscopy, energy and wavelength dispersive X ray spectroscopies and X ray photoelectron spectroscopy, we show that this deposition method can produce large area MoS2 films with high quality and uniformity over graphene. We reveal the potential of these heterostructures through demonstrating the operation of the structure as a prototype photodetector. These results pave the way towards developing the electrodeposition method for the large scale growth of heterostructures consisting of varying 2D materials for many applications.
author_names: Yasir J Noori

Shibin Thomas

Sami Ramadan

Danielle E Smith

Victoria K Greenacre

Nema M Abdelazim

Andrew L Hector

Norbert Klein

Gillian Reid

Phillip N Bartlett

C H De Groot
title: Large Area Electrodeposition of Ultra Thin MoS2 on Graphene for 2D Material Heterostructure Photodetectors
year: 2020

abstract: The societal impact of the electronics industry is enormous not to mention how this industry impinges on the global economy. The foreseen limits of the current technology technical, economic, and sustainability issues open the door to the search for successor technologies. In this context, molecular electronics has emerged as a promising candidate that, at least in the short term, will not likely replace our silicon based electronics, but improve its performance through a nascent hybrid technology. Such technology will take advantage of both the small dimensions of the molecules and new functionalities resulting from the quantum effects that govern the properties at the molecular scale. An optimization of interface engineering and integration of molecules to form densely integrated individually addressable arrays of molecules are two crucial aspects in the molecular electronics field. These challenges should be met to establish the bridge between organic functional materials and hard electronics required for the incorporation of such hybrid technology in the market. In this review, the most advanced methods for fabricating large area molecular electronic devices are presented, highlighting their advantages and limitations. Special emphasis is focused on bottom up methodologies for the fabrication of well ordered and tightly packed monolayers onto the bottom electrode, followed by a description of the top contact deposition methods so far used.
author_names: L Herrer

Santiago Martin

Pilar Cea
title: Nanofabrication Techniques in Large Area Molecular Electronic Devices
year: 2020