Background: In a prior post I showed that we had seeded cells on both nano- and micro-porous SiN Liftoff Membranes. The nanoporous proved to be rather weak and showed numerous broken windows after seeding the cells. Summary/Conclusions: In this follow up post, I seeded adipose derived stem cells on 50 nm thick microporous SiN liftoff membranes with…
In all of the below graphs, the x-axis has the same scale for easy comparison (-10 nm to 80 nm diameter). The Y-axis varies from plot to plot, but since we care more about pore density than actual numbers of pores, I have left these numbers out. Here is an example full plot with MATLAB’s…
The basic principle of inducing the osmotic pressure to suppress back pressure is based on the counterbalance of the opposing flows of solvent. Consider an electrolytic cell composed of a pair of Ag/AgCl electrodes and a Nafion-coated pnc-Si membrane separating NaCl solution into two halves. Initially, the electrolyte in either half has the same concentration…
Aminosilane has been used widely to derivatize the surface of silica for the applications in analytical chemistry, biochemistry, and biomedicine. It also plays an important role in providing adhesion for Nafion coating on silica surface. The basic principle is described as follows. After oxidizing the surface of silicon, the next step involves the derivatization of…
Previous posts: Theory Deposition Etching Imaging I have tinkered with the etch recipe some more, adding Argon to help prevent polymer formation (adding 5% O2 was not enough). The current recipe is 200 mTorr (100 mTorr Ar, 5 mTorr O2, 95 mTorr CHF3) at 120-125 W (6-12 W reflected). The plasma color is initially rosy (Argon), settling into a…
In the field of gas permeance there is a plot called the “Robeson Plot” (the paper that debuted it) that is used to compare the separation behavior of various membranes made of different materials and measured in different systems. An example is pictured: Various literature data for the log permeability of H2 gas versus the…
In my continuing efforts (previous post) to create a nanofluidic transistor, I recently repeated some of my earlier attempts to prototype a basic Si-Ag-Al2O3 stack. This time, however, I used SiN chips from wafer #1070 (<40 nm>). As before, I aimed for a ~3 nm Ti adhesion layer (4.3 nm actually) and a 12 nm…
In this post I’ve detailed my attempts and eventual success (with Josh’s help) to get the ALD to coat TEM grids without blowing the delicate chips around. The actual technique is at the end of the post, beginning with the picture of two valves. We use the Cambridge Nanotech ALD system for two purposes. First,…
Here are some images of deposited magnesium fluoride films on 50 nanonitride:
On Friday, Henry was kind enough to ship 15 tested Sepcons to the Barcikowski group in Essen, Germany. With luck they will arrive in time for Christmas. I wrote up some documentation and an illustration for wetting and using the Sepcons and figured I would share it with the group. Unfortunately, wordpress won’t let me…