Using YES system for PEG deposition
It was decided during my rotation-review meeting to use a smaller PEG molecule (3-mer) for silanization of pncSi. Following is the brief description of the polymer.
Boiling Point: 147-9°C @ 0.3mm Freezing Point: <0°C
Specific Gravity: 1.16 Vapor Pressure, 25°: <0.1mm
Vapor Density (air=1): >1 Solubility in water: soluble, reacts
% volatiles: NA Evaporation rate: NA
Molecular Weight: 326.46 Appearance & Color: Clear to straw liquid with mild odor
The boiling point is lesser than 150C, which can be vaporized in the YES system (T-max = 205 for YES). The protocol of deposition (adopted from Shestopalov’s lab) involves initial plasma-oxidation of the silicon surface. Later, they used to take 30 ul of PEG silane (6-9 mer) and 10 ul of filtered tri-ethylene amine (as a base) in separate open glass vials, and allowed the vacuum to deposit the PEG on the silicon substrates. The deposition was done at RT for 18 hours. I believe we can perform all this chemistry in our YES system. We now have the advantage of actually vaporizing the silane, creating better vacuum, and providing much cleaner environments for deposition. From my understanding, we can use the injection port to vaporize the silane to deposit on pncSi. I was wondering if this might interfere from/with Adarza’s operation, but that is something which can be sorted out. I believe that, once the recipe is fed to YES system then we can test this process easily.
Any comments?