21553-10
Silicon Nitride membranes have been modified using Atomic Layer-Deposited (ALD) techniques to change their surface properties. Depending on the process used, both Hydrophilic and Hydrophobic substrates have been created with the following advantages:
Hydrophobic surfaces improve sample preparation for materials that are dissolved or suspended in organics solvents.
Nanoparticles in organic solvents (such as carbon nanotubes) will readily disperse on the Silicon Nitride membrane surface.
Hydrophilic surfaces enhance wetting and dispersion of aqueous solutions.
This avoids particle aggregation effects commonly observed on less hydrophilic surfaces.
Particularly useful in water based sols and life science applications.
Both coatings are available on 50nm and 200nm PELCO® Silicon Nitride Membranes with a 0.5 x 0.5mm window and 15nm Si3N4 membrane with 9 each 0.1 x 0.1nm windows on a 200µm silicon frame with a diameter of 3mm, compatible with all standard TEM grid holders.
Both sides of the membrane and frame are coated.
We advise to handle the discs by gripping at the edge.
SURFACE | SURFACE ENERGY (mJ/m2) | STANDARD DEVIATION |
Silicon Nitride Membrane | 46.1 | 4.3 |
Hydrophilic Coating | 76.1 | 2.2 |
Hydrophobic Coating | 24.6 | >4.4 |
mj= millijoules |
SURFACE | SURFACE ROUGHNESS (nm) | STANDARD DEVIATION |
Silicon Nitride Membrane | Rq=0.65 Ra=0.45 |
0.06 0.02 |
Hydrophilic Coating | Rq=0.57 Ra=0.40 |
0.04 0.03 |
Hydrophobic Coating | Rq=0.66 Ra=0.40 |
0.03 0.05 |
Rq= Surface Roughness; Ra= Roughness Average |