| ALD of Al2O3
|
energy analysis |
precursor utilization,
methane emissions, and nanowaste generations |
energy
flow analysis demonstrates that the ALD process energy
consumption is mainly determined by the ALD cycle time rather than
the process temperature |
(44) |
| ALD of Al2O3
|
exergy analysis |
energies
associated with material, heat, and work flow |
utilization
of energy is extremely low in ALD Al2O3 process |
(49) |
| ALD of Al2O3
|
LCA |
cradle-to-grave |
ALD produces the highest environmental
impact in the category
of fossil fuel use; the impacts associated with the auxiliary infrastructure,
equipment, and tools for ALD operation are intensive mainly due to
the slow ALD cycling process |
(45) |
| ALD of Al2O3
|
gas and aerosol emissions analysis |
process emissions at the exhaust |
CH4 and C2H6 generated, emissions
of ultrafine particles (diameter <100 nm) reduce with longer purging
time |
(46) |
| ALD of Al2O3
|
DFT calculations on process wastes and methane emissions |
chemical reaction of the process: 2Al(CH3)3 + 3H2O → Al2O3 + 6CH4
|
high material waste (up to 60% of precursors);
waste generated
and methane emissions increase with pulse time; the moderate temperature
of the chamber (200 °C) leads to less waste |
(47) |
| ALD of Al2O3
|
gas and nanoparticles
emissions analysis |
process emissions at the exhaust |
93% of TMA is discarded as waste; nanoparticles generated are
harmful to humans; emissions decrease with purge time |
(48) |
| ALD of Al2O3
|
computational
analysis |
10-wafer ALD processing system emissions |
Al203 nanowastes generated from the ALD
production system are grave concerns |
(56) |
| ALD of Zn(O,S) to replace CdS as buffer layer in CIGS photovoltaic
cells |
LCA |
front end of a CIGS module |
ALD has 19–26 times lower
environmental impacts than chemical bath deposition (CBD) of CdS for
all categories but metal depletion (2.65 higher) |
(57) |
| ALD of ZnO |
LCA |
gate-to-gate |
majority of the impact is related to electricity consumption,
and material usage is of minor importance |
(58) |
| Plasma-enhanced CVD (PECVD) of amorphous silicon (a-Si:H)/nc-SiOx,/SiNx and ALD
of Al2O3 for silicon heterojunction solar cells |
LCA |
complete solar PV installation |
new SHJ designs based on PECVD and ALD have a better environmental
performance compared to the reference SHJ design; PECVD requires more
energy for thin film deposition than ALD |
(59) |
| low-pressure CVD (LPCVD) of TiO2
|
material and energy consumptions analysis |
material consumption: Ti(OC3H7)4(g) + 2H2O(g) → TiO2(s) + 4C3H7OH(g) |
precursor and energy
utilization efficiencies
< 1% |
(60) |
| Energy consumption:
Energy for heating the reactor, energy
for pumping, energy absorbed by the input gases, and energy of the
chemical reaction |
| plasma-assisted CVD (PA-CVD)
of SiOx
|
LCA |
1 m2 surface protected by a layer with a thickness
of 1 μm |
PA-CVD
involves high gross energy requirement (GER) and global
warming potential (GWP) values |
(61) |
| CVD of TiCN-TiN-Al2O3
|
LCA |
cradle-to-gate |
thin film deposition process accounts
for less than 10% of
the total manufacturing energy of inserts for cutting tools; CVD is
more energy-demanding than PVD |
(62) |
