Molecular Beam Epitaxy

Growth & Synthesis (Physical depositions of thin films)

Molecular beam epitaxy (MBE) is a growth technique for the deposition of high quality and high purity epitaxial layers on suitable substrates. It is mainly used for the growth of semiconductors, oxides and organic materials.

Fully automated MBE systems for the growth of advanced, compound semiconductor heterostructures, composed of compounds based on III-Arsenide, III-nitride, Si, SiC, Ge, C semiconductor nanostructures with sub-nanometer control of the film thicknesses. The MBE system is used to make nanostructures, including quantum dots and nanowires, and epitaxially layered structures and heterostructures, for the fabrication of lasers, photodetectors, light-emitting diodes and other optoelectronic devices. The MBE systems are equipped with a series of in-situ analytical characterization tools for continuous monitoring of the growth process.

Thermally produced atomic or molecular beams of the constituent materials migrate in Ultra High Vacuum (UHV) environment until impinge on a heated substrate where they are incorporated. The growth rate is generally very slow, of the order of one monolayer (ML) per second, allowing a ML control of the deposition.

The UHV environment allows for the use of diagnostic techniques during the growth as the reflection high energy electron diffraction (RHEED) and the integration of the growth system with UHV surface characterization techniques. When combined with the referred ability to perform in-situ high-resolution structural and electronic diagnostics of the films as they are being deposited, MBE provides the ideal scenario for understanding many of the fundamental structural and physical properties of ultrathin inorganic and organic film systems.

In some cases, MBE systems should be prepared not only for in-situ characterization but for in operando as well, in order to study the dynamics of growth. This should lead to the design of compact, element or material specific and flexible systems. In operando studies are particularly interesting for understanding catalytic processes.

 

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          provided at NFFA-Europe laboratories by:
CNR-IOM (TS)
Italy
C2N-CNRS
France
CSIC-ICMAB
Spain
FORTH
Greece
JCNS @MLZ
Germany
EURONANOLAB
France
CNR-IOM (TS)
Italy
III-V and II-VI MBE
III-V and II-VI MBE
For III/V materials: effusion cells for Ga , Al, In, As, Si (n-type dopant), GaTe (n-type dopant) and Be (p-type dopant), RF Plasma source for N; for II/VI materials: effusion cells for Zn, Cd, Se, Te
III/V materials: GaAs, AlGaAs, InGaAs epitaxial layers and nanowires; II/VI materials: ZnSe, ZnCdSe epitaxial layers and nanowires; In mounted; dimension up to 3" diameter; T range: up to 700°C for III/V materials and up to 500°C for II/VI materials
UHV
RHEED gun 10 kV
Metallization chamber for deposition of Au and Al at room temperature
XPS analysis chamber with Al Kα source
CNR-IOM (TS)
Italy
Oxide MBE
MBE of metal oxide ferromagnetic, antiferromagnetic, superconducting, insulating, ferroelectric, multiferroic ; MBE masked conducting deposition
Sources for Oxide-MBE growth: 3 high temperature effusive cells (up to 1500°C); 3 conventional effusive cells; 2 low temperature effusive cells; ozone/oxygen deposition pressure up to 10-5 mbar; 3d, 4d, 4f metals, organic molecular magnets, MgO, Al2O3, NiO; perovskite structure compounds ABO3: ( La-Sr)(Co-Cu-Ti-Zn)O3, (Ba-K)(Cu-Bi)O3, (Ba-Sr)(Ti-Zr)O3, (La-Ba)(Mn-Fe-Ni-Co)O3, Bi(Fe-Mn)O3; Spinel structure compound AB2O4: ZnFe2O4, Fe3O4 Sources for MBE Masked conducting deposition: Au, Pd, Fe, Co, Mn conductive metals, up to 5 e-bombardment evaporators.
For Oxide-MBE growth: dimensions up to 10x10mm2; T up to 800K For MBE Masked conducting deposition: dimensions up to 5x5mm2; T range: 35-300K; annealing temperature up to 950K
For Oxide-MBE growth: base pressure down to 10-9 mbar
For Oxide-MBE growth: 2 RHEED guns, electron energy 10 kV, spot size 100 micron diameter; RHEED software analysis KSA-400 For MBE Masked conducting deposition: LEED/Auger spectroscopy OCI BDL800IR; transport measurements Keithley 6487
For MBE Masked conducting deposition. XPS Chamber with: Al and Mg K-alfa X-rays at 1486.7 and 1253.7 eV, electrostatic hemispherical analyzer (radius 200 mm), T range 25-300 K; MOKE magnetometry with: HeNe Thorlabs HNL020L laser 632.8 nm, linear polarization, T range 30-340 K, maximum H-field 0.55 T in UHV, 0.75 T in air, minimum H-field step 0.3 mT, pole face diameter 76 mm, frequency filter HINDS optical chopper 50KHz, Si, Ge photodiode HINDS DET 200-004, spectral range 350-1100 nm
CNR-IOM (TS)
Italy
High Mobility MBE
High Mobility MBE
Effusion cells for Ga (2x), Al, In, As, As cracker. Doping: Si (n-type) and C (p-type) direct-heat filament
III/V materials: GaAs/AlGaAs 2D electron gases with low-T electron mobility up to 8X106 cm2/Vs, metamorphic In0.75GaAs/In0.75AlAs quantum wells with low-T electron mobility up to 5X105 cm2/Vs, photonic structures, self-assembled quantum dots on planar and patterned surfaces; dimension up to 2" diameter; T range: up to 700 C; possibility of In-free mounting
UHV
RHEED gun 15 kV
Magnetotransport facility
CSIC-ICMAB
Spain
SiGe MBE
MBE SiGe epitaxy
Si e-beam and Ge effusion cell for deposition at typical fluxes ~0.05nm/s; dopant sources for C, B, and Sb with typical fluxes up to ~0.0005nm/s
Substrate sizes up to 10cm (4") diameter wafers, also possible from 1 to 4 cm2 square substrates; In-free mounting; T range: up to 950° C
Base pressure in growth chamber in 10-10 mbar range
RHEED gun 30 kV allows observation for big substrates
Ex-situ optical and electrical basic characterization possible (f.i., ellipsometry, Raman, and Hall measurements), no analysis software available
FORTH
Greece
III-As MBE
MBE of heterostructures & nanostructures, dots and NWs for nano and optoelectronic applications
K-cells for Ga (2), Al (2), As, In, Si, Be
Dimension up to 3"
UHV
RHEED 15 KeV; mass spectrometer 1-300 amu
Preparation chamber with outgas heater and Auger spectrometer
FORTH
Greece
Group IV elements MBE
c-SiC growth, SiC NWs
K-cells for Ga, Ge, Al; C2H2 gas sources; e-guns for Si and C
Dimension up to 3"
UHV
RHEED 30 KeV; mass spectrometer 1-300 amu
Preparation chamber with outgas heater and Auger spectrometer, substrate heater up to 1200oC
FORTH
Greece
III-Nitrides MBE
MBE of heterostructures & nanostructures, dots and NWs for nano and optoelectronic applications
K-cells for Ga, Al, In, Si; additional Si sublimation source; N2 RF plasma source; NH3 possible too
Dimension up to 3"
UHV
RHEED 15 KeV; mass spectrometer 1-200 amu
Preparation chamber with outgas heater
JCNS @MLZ
Germany
Thin film MBE
Thin film fabrication Detailed information is available at https://mlz-garching.de/mbe
4 high temperature effusive cells (up to 1800°C); 2 low temperature effusive cells (up to 1400°C); plasma source for oxygen/nitrogen (plasma up to 600W) with deposition pressure up to 10-5mbar; 2 e-guns with 4 crucibles; typical evaporation materials: Fe, Co, Au, Ag, Ni, Sr, Ti, Mn, Nb, Pt, Cu, Cr, other materials on request.
Dimensions up to 10x10mm2; T up to 1000°C
Base pressure down to 10-10 mbar
RHEED gun, electron energy 20 kV, RHEED software analysis KSA-400; LEED up to 1 kV; AES up to 5 kV; residual gas analyzer; quartz micro balance
Script based programming of sample preparation/growth A new offer is a special transfer chamber allowing the transfer and measurement of thin films under UHV conditions. After growth of the thin film samples with the MBE setup, they can be transferred into the transfer chamber without breaking the vacuum. The samples can be measured with MNR (Installation 6, Characterisation) at a pressure better than 10-9 mbar at room temperature and in magnetic fields up to 300 mT.
Additional sample characterization in the laboratory like Atomic Force Microscopy (AFM), see installation 4, characterisation AFM.
C2N-CNRS
France
III-V MBE 2DEGs and quantum cascade structures
III-V MBE: 2DEGs and GaAs/AlGaAs quantum cascade structures
Effusion cells for Ga (2x), Al (2x), In, As cracker. Doping: Si (n-type) and C (p-type) direct-heat filaments
III/V materials: GaAs/AlGaAs 2D electron gases with low-T electron mobility up to 2.5X106 cm2/Vs, with a possibility of 2DEGs on sub-micron membranes, GaAs/AlGaAs quantum cascade structures; dimension up to 2" diameter; T range: up to 700°C; possibility of In-free mounting
UHV
RHEED gun 12 kV
Magnetotransport facility
C2N-CNRS
France
III-V MBE with PL, FTIR and magnetotransport
MBE growth of a large range of III-V material: microcavities, quantum dots, electro-optical devices
7 effusion cells (2xGa, 2xAl, In, Si, Be), As, P, Sb cracker cells, N plasma source
Up to 2" wafer, GaAs, InAs, InP, GaSb substrates, T up to 900°C
Base pressure down to 10-10 torr
RHEED gun 12 kV
Outgassing chamber
PL setup (down to 77K), FTIR microscope, magnetotransport facility
C2N-CNRS
France
III-N MBE
MBE of nitride based nanowires
5 effusion cells (Ga, Al, In, Si, Mg); N plasma source
Wafer dimension: 1/4 of 2"; T up to 850°C
UHV
RHEED gun 15 kV
C2N-CNRS
France
III-V MBE microcavities, quantum dots and electro-optical devices
MBE growth of a large range of III-V material: microcavities, quantum dots, electro-optical devices
7 effusion cells (2xGa, 2xAl, In, Si, Be), As, P, Sb cracker cells, N plasma source
Up to 2" wafer; GaAs, InAs, InP, GaSb substrates; T up to 900°C
Base pressure down to 10-10 torr
RHEED gun 12 kV
Outgassing chamber
C2N-CNRS
France
III-V MBE diluted magnetic semiconductors
MBE growth of III-V diluted magnetic semiconductors
7 effusion cells (Ga, Al, In, P, Si, Be, Mn), As cracker cell
Up to 2" wafer; GaAs, InAs, InP substrates; T up to 700°C
UHV
RHEED gun 15 kV
Outgassing chamber
C2N-CNRS
France
III-V MBE nanowires
MBE growth of III-V nanowires, equipped with a gold cell in the growth chamber for catalyst
6 effusion cells (Ga, Al, In, Si, Be, Au), As, P cracker cells
Up to 2" wafer; GaAs, InAs, InP substrates; T up to 700°C
UHV
RHEED gun 15 kV
Outgassing chamber