Structural analysis of amorphous Si films prepared by magnetron sputtering

Grozdanić, D.; Slunjski, Robert; Rakvin, Boris; Dubček, Pavo; Pivac, Branko; Radić, Nikola; Bernstorff, Sigrid

doi:10.1016/j.vacuum.2009.05.014

Cited by 5 publications

(4 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Amorphous Si thin films could be rendered porous or dense by changing the sputter-deposition rate and the pressure. During unbalanced magnetron sputtering [31,32] the density (or inversely the porosity) of the deposited film can be steered by controlling the collision rate of the deposited species with the plasma species. Reduced collision rates lead to deposited species impacting the substrate with high energies, and therefore to denser films [31,32].…”

Section: Experimental Methodsmentioning

confidence: 99%

“…During unbalanced magnetron sputtering [31,32] the density (or inversely the porosity) of the deposited film can be steered by controlling the collision rate of the deposited species with the plasma species. Reduced collision rates lead to deposited species impacting the substrate with high energies, and therefore to denser films [31,32]. Indeed, we found that fast deposition rate (above 1.5 nm min −1 ) and high pressure (above 20 mTorr) resulted in porous films (PM), whereas slower deposition rate (below 1.5 nm min −1 ) at lower pressure (below 20 mTorr) conducted to denser films (DM) [31,32].…”

Section: Experimental Methodsmentioning

confidence: 99%

“…Reduced collision rates lead to deposited species impacting the substrate with high energies, and therefore to denser films [31,32]. Indeed, we found that fast deposition rate (above 1.5 nm min −1 ) and high pressure (above 20 mTorr) resulted in porous films (PM), whereas slower deposition rate (below 1.5 nm min −1 ) at lower pressure (below 20 mTorr) conducted to denser films (DM) [31,32]. If the PM is too thick, it wrinkles, swells, and buckles, and its internal stress actually causes pattern collapse.…”

Section: Experimental Methodsmentioning

confidence: 99%

“…In both cases, after the polymer assembly (directed or undirected), the film is exposed to UV radiation to scission the PMMA block and to crosslink the PS. A thin permeable Si membrane (PM, ∼1 nm thick) is deposited by magnetron sputtering [31,32] on top of the polymer film. The structure is then immersed in acetic acid [30] to selectively remove the PMMA block through the porous permeable membrane resulting in a mesoporous PS film with a suspended Si membrane on top.…”

Section: Fabrication Proceduresmentioning

confidence: 99%

See 3 more Smart Citations

Three-dimensional mesoporous structures fabricated by independent stacking of self-assembled films on suspended membranes

Rose¹,

Bosworth²,

Dobisz³

et al. 2010

Nanotechnology

View full text Add to dashboard Cite

We report an original iterative method for fabricating three-dimensional mesoporous structures by independently stacking multiple self-assembled block copolymer films supported by Si membranes. A first layer is formed on the substrate by a self-assembled PS-b-PMMA (polystyrene-block-poly(methyl methacrylate)) film. A porous, permeable Si membrane deposited on top of the first block copolymer film provides mechanical support, preventing pattern collapse during the wet developing used to selectively remove the PMMA component of the PS-b-PMMA film. A second, dense Si membrane is deposited to seal the porous membrane, resulting in an impermeable coating suspended atop the self-assembled mesoporous polystyrene structures. The process can then be iterated using the sealed membrane as the new substrate to support a subsequent self-assembled block copolymer film. This multilayer approach provides a flexible three-dimensional fabrication technique where, in each layer, pattern morphology, domain orientation and degree of ordering can be designed independently. Furthermore, the process is compatible with electron-beam directed assembly, used to achieve regular patterns with feature density multiplication at any level in the stack.

show abstract