What kind of film can be deposited on a laboratory tubular PECVD electric furnace?

The laboratory tubular PECVD electric furnace can deposit various types of thin films on various substrates through plasma enhanced chemical vapor deposition technology. The coating types are wide and the performance is excellent. The specific coating types and characteristics are as follows:

1. Inorganic non-metallic thin film
Silicon-based thin film
Amorphous silicon (a-Si):
Features: High light absorption coefficient, adjustable bandgap, suitable for solar cell light absorption layer.
Applications: amorphous silicon solar cells, active layers of thin film transistors (TFTs).
Microcrystalline silicon (μ c-Si):
Features: Grain size 1-100nm, combining the high absorption of amorphous silicon with the high mobility of crystalline silicon.
Application: Bottom layer of stacked solar cells, high mobility TFT.
Silicon nitride (Si ∝ N ₄):
Features: High hardness, excellent chemical stability, adjustable refractive index, dense without pinholes.
Application: Passivation layer for solar cells, protective layer for MEMS devices, optical anti reflection coating.
Silicon oxide (SiO ₂):
Features: High transparency, low refractive index, good insulation.
Applications: Gate oxide layer, multi-layer optical film substrate, semiconductor device isolation layer.
Silicon carbide (SiC):
Features: high hardness, high thermal conductivity, wide bandgap.
Application: High temperature semiconductor devices, wear-resistant coatings, LED heat dissipation layers.
Oxide thin film
Aluminum oxide (Al ₂ O3):
Features: High chemical stability, excellent insulation.
Application: Passivation layer on the back of solar cells, MEMS capacitor dielectric layer, anti-corrosion coating.
Zinc oxide (ZnO):
Features: High transparency, n-type conductivity.
Applications: Transparent conductive oxide (TCO) thin films, window layers for thin-film solar cells, and surface acoustic wave devices.
Titanium dioxide (TiO ₂):
Features: High refractive index, excellent photocatalytic activity.
Applications: Photocatalytic coatings, self-cleaning glass, dye-sensitized solar cell photoanodes.
nitride film
Aluminum nitride (AlN):
Features: high thermal conductivity, wide bandgap, good piezoelectricity.
Applications: Heat dissipation layer for high-power electronic devices, piezoelectric layer for surface acoustic wave devices, LED substrate.
Gallium Nitride (GaN):
Features: Wide bandgap, high electron mobility, high temperature and pressure resistance.
Applications: Blue LED, high-power RF devices, UV detectors.

2. Composite thin film and doped thin film
Silicon based composite film
Silicon oxide nitrogen (SiON):
Features: The refractive index can be continuously adjusted by adjusting the Si, O, and N ratios, compatible with CMOS technology.
Application: Gradient refractive index anti reflective coating, optical waveguide, passivation layer for semiconductor devices.
Silicon carbon nitrogen (SiCN):
Features: High hardness, excellent oxidation resistance, temperature resistance up to 1000 ℃.
Application: High temperature protective coating, tool wear layer, aviation engine components.
Doped thin film
Phosphorus doped amorphous silicon (p-a-Si: H):
Features: p-type conductivity, adjustable bandgap.
Application: p-type layer of amorphous silicon solar cells, TFT source/drain.
Boron doped silicon nitride (B-Si ∝ N ₄):
Features: Reduce the deposition temperature to 200 ℃ and improve the stress distribution of the thin film.
Application: Passivation layer on flexible substrates (such as polyimide), protective layer for MEMS movable structures.

3. New functional film
two-dimensional materials
Hexagonal boron nitride (h-BN):
Features: atomically flat surface, high thermal conductivity, wide bandgap.
Applications: Graphene heterojunction substrates, deep ultraviolet light-emitting devices, and insulation layers for high-power electronic devices.
Graphene like carbon nitride (g-C ∝ N ₄):
Features: Excellent photocatalytic activity, bandgap, visible light response.
Application: Photocatalytic decomposition of water for hydrogen production and degradation of organic pollutants.
Nanostructured thin films
Silicon nanowire array:
Features: High light absorption efficiency, excellent carrier transport performance.
Application: Negative electrode material for radial junction solar cells and lithium-ion batteries.
Silicon nitride nanoporous film:
Features: controllable pore size, high porosity, high mechanical strength.
Applications: DNA sequencing, nanofluidic devices, filtration and separation membranes.

4. Suggestions for selection and process optimization
Film type selection:
Determine the thin film material system based on application requirements such as optical, electrical, and mechanical properties.
For example, solar cells require high light absorption/passivation performance, and amorphous silicon/silicon nitride is preferred; Flexible electronics require low-temperature deposition and can be optionally doped with silicon nitride.
Process parameter regulation:
Gas flow ratio: Adjust the SiH ₄/NH ∝/N ₂ ratio to control the composition and refractive index of the Si ∝ N ₄ film.
RF power: Increasing power enhances plasma density, increases deposition rate but may increase film stress.
Temperature gradient: The gradient distribution of film composition/structure is achieved through a multi temperature zone furnace body (such as SiON gradient refractive index film).
Device compatibility:
Confirm whether the equipment supports multi gas mixing, in-situ monitoring, and integration with PVD/ALD to expand the process range.