CVD / Chemical Vapor Deposition
Chemical Vapor Deposition (CVD) is a process used to produce conformal thin film materials onto rigid or flexible substrates from the gaseous phase of one or more chemical precursors, which react with (and/or decompose on) the substrate surface. Depending on the CVD technique (e.g., LPCVD, PECVD, Hot filament/Catalytic CVD) and process conditions (substrate material, temperature, pressure, gas flow(s), reaction gas composition, etc.), various materials (e.g., Si, SiO2, Si3N4, SiC, transition metals, ZnO, carbon nanotubes, graphene) with a wide range of physicochemical properties can be grown. As deposition is controlled by chemical reaction of volatile precursors with the substrate surface, CVD can produce highly conformal coatings on structures of complex topography. CVD is widely used in the semiconductor industry for the fabrication of integrated circuits, optoelectronic devices, sensors, micro-electromechanical systems, solar cells, etc.
Home-made CVD system using 3-zone programmed heating elements
Transition metal dichalcogenides (TMDChs) such as MoS2, MoSe2, WS2, WSe2, TaS2, etc., deposited either on Si substrates or on the corresponding transition metal foil. Zinc oxide (ZnO) nanostructures on Si substrates.
S, Se, Te, Ar, N, Ar/H
Maximum temperature 1200oC
3×3 cm2 (max)
Growth of TMDChs, VLS growth of ZnO, etc.
Dr. Spyros N. Yannopoulos, firstname.lastname@example.org
Three home-made, Fully automated CVD reactors
Horizontal Low Pressure CVD, Horizontal Atmospheric Pressure CVD, Vertical Hot-Wire Low Pressure CVD.
W, Cu, WOx (x≤3), MoOx (x≤3), SnO2 (undoped and doped with: F, Er, Sb, P, Si, Ge), Va2O5, Ta2O5, Cu2O, MoS2.
Various chlorinated, metal-organic and organo-metallic precursors and dopants.
Other Gases: Nitrogen, Oxygen, Argon, Hydrogen, Hydrogen Sulfide.
Dependent on the deposited film, from room temperature up to 600oC. Pressures varying from atmospheric to 100 mTorr.
From samples of 1x1cm2 to 3” wafers
Metals (Cu, W), diffusion barriers (W), Hole or/and electron selective layers (WOx , MoOx) for Organic Light-Emitting Diodes and Solar Cells (OLEDs, OSCs), Electrochromic windows and Displays (WO3, MoO3), Insulators (Ta2O5) for gates and intermetal dielectrics for large area electronics, Transparent Conductive Oxides (SnO2 undoped and doped) for optoelectronics. Semiconductors for large area electronics (MoS2).
Dr. Dimitris Davazoglou, email@example.com
Vacutec/1500 series plasma system
PECVD, combo with RIE system (RF Frequency: 13.56MHz)
Silane in N2, Ammonia, Nitrogen
Temperature: 20 – 300oC
RF power: 20-200W
From samples of 1cm x 1cm up to 5 wafers of 4” in diameter
Passivation Coatings, Anti-reflective Coatings, RFMEMS dielectric, capacitor dielectric, etc.
George Stavrinidis, firstname.lastname@example.org
Home-made CCVD apparatus consisting of a Carbolite tubular furnace and two Omega digital mass flow-meters
Catalytical Chemical Vapor Deposition (CCVD) system
Various hydrocarbon (H/C) gasses (carbon precursor): acetylene, methane, ethane, propane, etc; carrier (inert) gases: argon, nitrogen.
Temperature up to 1000oC
H/C gas flow rate up to 20 cm3/min
Carrier gas flow rate up to 200 cm3/min.
Ceramic or alumina crucibles for powder samples (capacity up to 50 ml); substrate size up to 10cm x 1.5cm
Growth of carbon nanostructured materials including single- and multi- wall carbon nanotubes and graphene; Carbonization process; Pyrolysis; Annealing of materials.
Prof. Dimitrios Gournis, email@example.com