Laboratoire de Physique des Interfaces et des Couches Minces

CNRS - École polytechnique - Institut Polytechnique de Paris

In situ and real-time observation of nanocrystal growth in « NanoMAX », a modified ETEM

Written by : Ileana Florea

lenuta-ileana.florea@polytechnique.edu

“NanoMAX”, a modified environmental transmission electron microscope (ETEM), joined the CIMEX platform in 2015 https://portail.polytechnique.edu/cimex/

The NanoMAX project is part of the “TEMPOS “Equipex ( http://www.tempos.fr/) funded by the French Governement “Investissement d’Avenir” program. TEMPOS stands for Transmission Electron Microscopy at Palaiseau, Orsay and Saclay and it gathers the efforts of the  Paris-Saclay University (UPSaclay), Ecole polytechnique, CNRS, and CEA to create a world-class center for transmission electron microscopy (TEM) in the Paris-Saclay area.

The NanoMAX microscope, unique in its design, allows in situ and real-time observation of nanocrystals growth  (nanowires and quantum dots of semiconductors, carbon nanotubes, lamellar materials, and other nano-objects). It allows us to understand, at the atomic scale, the mechanisms that govern their growth.

Two partners have developed the means of growth of this microscope: the LPICM (UMR 7647, CNRS, École polytechnique, IPParis) and the C2N (UMR 9001, CNRS, Université Paris-Saclay). These two laboratories bring together long expertise in transmission electron microscopy and crystal growth of nanomaterials.

The first experiments carried out aimed at the development of new functional objects, which can be used in devices (for example field-effect cathodes for power transmitters based on carbon nanotubes, photovoltaic cells integrating nanomaterials, chemical and biological sensors. , nano-transistors or nano-lasers).

In 2021 NanoMAX joined the national network METSA (https://metsa.ows.fr/) a French research federation made up of 9 platforms, bringing together a set of state-of-art expertise and equipment.

NanoMAX microscope description with its technical specifications as well as the scientific expertise of people in charge of the experiments

Expertise

Nano-objects growth: Semiconductors (III-V, II-VI) by MBE; Semiconductors withs hydrides or organométallics by CVD; RaCVD under electric field; Carbon-based by CVD, RaCVD; Nitride type by RaCVD;

In situ treatments under differents environments: O2, H2,

Low dose observations  (5-20 e-.Å-2.s-1)

HR-TEM image corrected

STEM-HAADF

TEM/STEM-EDX

Technical specificities and performances

Environmental TEM TITAN G2 60kV, 80kV et 300kV

Image Cs Corrector (résolution 100 pm à 80 et 300kV)

Matter Source: molecular beams produced by effusion sources (MBE); radicals produced by thermal cracking (RaCVD); radicals produced by plasma cyclotron (RaCVD); gas sources(CVD)

Mode MBE 10-8 mbar: effusion sources: Ga, In, As, Sb, Te, Ge,…

Mode ETEM  10-3 mbar : gas sources: CXHX, SiH4, PH3, GeH4, TMGa; H2, O2, N2

Specimen Stages: Two standard sample holders, one single tilt and one double tilt; Two heating sample holders (Fusion-Protochips ) specially design allowing reaching temperature range (25-1200°C); One liquid electrochemistry sample holder  (Poseidon 510-Protochips

Cameras: US1000 (2k×2k) with a recording speed of 4 fps (1k×1k); K2-IS DDE (4k×4k)  low dose (5-25 électrons.Å-2s-1) with a recording speed of 400 fps( 2k×2k) ; 800 fps(2k × 1k) and 1600 fps (2k × 0.5k ).

QMS 220 PrismaPlus de Pfeiffer Residual Gas Analyzer (RGA) allowing detection of reactants and products with a range of 1–100amu:

System EDX SDD X-max

People Involved in the NanoMAX project 

LPICM : Jean-Luc Maurice (scientific coordinator), Ileana Florea (person in charge with the equipement, and METSA local contact), Costel-Sorin Cojocaru, Éléonor Caristan, Didier Pribat, Pavel Bulkin.

C2N : Jean-Christophe Harmand (scientific coordinator),  Gilles Patriarche, Federico Panciera, Laurent Travers ,Ludovic Largeau, Daniel Bouchier, Laetitia Vincent, Charles Renard, , Frank Glas;

CEA-DSM-IRAMIS : Martine Mayne, Emeline Charon, Mathieu Pinault

Short video presenting the ETEM equipement