Metallized membranes
I took a closer look at some of Lingyun’s samples today, and captured some interesting TEM images.
wafer 205 with 10 nm Ti @ 35kx
wafer 205 with 10nm Ti @ 250kx
wafer 205 with 10nm Ti & 10nm Au @ 35kx
wafer 205 with 10nm Ti & 10nm Au @ 200kx
The higher mag. images show that the metallic film creeps over the pore (you can see the outline of the original pore, and it’s reduced dimension due to the metal coating).
For the Ti + Au coating, the pore shape is much more irregular, presumably due to the thicker film. Is there a way to optimize the coating so that we can retain the roundness of the pore?
It will also be interesting to measure the conductivity across these films, to confirm their continuity.
Is vacuum broken between the TI and Au depositions? This looks like poor adhesion to me given the open areas between the grains and the gold balls on the edge of the pore in the magnified image. When chromium or Ti are used as adhesion layers, it is very rare to break vacuum, presumably because they oxidize quickly, killing the adhesion…