A few weeks ago, professor Mike Aziz in Harvard University helped to annealed two samples and in-situ imaged the early stage of pore formation using their Jeol2010-hot-stage-TEM. The oxide seemed intact during the process. The sample was unannealed 20(bottom)/15(a-si)/10(top) three stack with removing the substrate. The first sample was heating to 693C. They took one…
Two high school students, Nick and Nikita, were supervised to study the effects our Sepcon membranes had on potential charge based separations. Using standard 30 nm cutoff Sepcons and the pressure cell, they performed a set of experiments with high (1 M) and low concentration (100 mM) KCl. They measured the conductivity of the filtrate…
To this point, I have shown that our membranes are stable with the use of INT’s developer over time. I have also shown that their developer has statistically similar flow properties to that of water, and is a viable option to pass through our membranes. This post will discuss the possibility of using their unique…
The thickness of bottom oxide in the ‘sandwich structure’ is also a key factor to affect the pore morphology. In last few weeks I deposited five wafers with different bottom oxide thicknesses and they were 05/15/20, 10/15/20, 20/15/20, 40/15/20 and 100/15/20. Then I annealed them at 1000C for 1 minute with a 100C/s ramp rate….
Last few weeks, I deposited a couples of wafers to test the effect of oxide thickness on pores. In addition to previous data, I deposited another two wafers, one with 1nm top oxide and the other with 100nm top oxide. I summed up all data from the top oxide experiments. The first image is the…
This experiment compares the metal developer used in Integrated Nano Technologies’ device to to the flow properties of water. Using the pressure cell at 3 psi, with no allyl treatment, for 10 minutes, and 200 microliters of liquid, I pushed water and developer through our membranes and examined the difference in flow rates. All of…
This is a continuation of the initial experiments testing the possibility of creating porous Si membranes with thicknesses ranging from 50 to several hundred nm, and mean pore diameters from ~50-200 nm. As suggested, we’ve started using 200 µm thick wafers and we’ve patterned with the Cell Culture mask as well as the Deflection Mask….
EO permeability: We often refer to the ‘efficiency’ of EO with pnc-Si as being very high, but this may not be the case. What is actually high, as in the case of the other modes of transport, is the ‘permeability’ in EO. Dimensionally, the quantity we’ve referred to (in various places) as the ‘efficiency, the…
This post relates to the ongoing project and potential grant between Integrated Nano-Technologies, Simpore, and NRG. The goal of my research is to show that our membranes can be integrated into Nano-Technologies’ device. Our membranes must be able to filter out or hold back large debris that can cause false positives in their device, while…
We are proposing a novel method for the fabrication of porous thin-film silicon membranes. It has been shown that metallic nanoparticles on the surface of silicon submerged in a solution of hydrofluoric acid and hydrogen peroxide will bore holes into the silicon. This selective etching occurs because the metal acts as a catalyst in the…