TY - JOUR
T1 - Hydriding kinetics of Pd capped YHx switchable mirrors
AU - Van Der Molen, S. J.
AU - Kerssemakers, J. W.J.
AU - Rector, J. H.
AU - Koeman, N. J.
AU - Dam, B.
AU - Griessen, R.
PY - 1999/12
Y1 - 1999/12
N2 - The kinetics of the metal-insulator transition in polycrystalline, Pd-capped YHx switchable mirrors upon hydrogenation is investigated. Using the accompanying optical transition, we study switching of matrix-like samples with many (∼200) combinations of Pd and Y layer thicknesses. We find that: (i) With increasing Y thickness dY, the switching time τ increases for any constant Pd thickness dPd. (ii) With increasing dPd, there are three regimes. In regime I, it is impossible to switch a device. This can mainly be related to Pd-Y compound formation consuming all Pd within the UHV system, followed by surface oxidation in air. In regimes II and III switching is possible, but only in regime III does Pd form a closed cap layer. The Pd thickness needed for a closed cap layer depends on dY. (iii) An oxide buffer layer hinders Pd-Y interdiffusion, so that a thinner Pd cap layer is needed for switching than in the case without buffer layer. This is interesting for potential applications since it yields a higher optical transmission in the open state of the device.
AB - The kinetics of the metal-insulator transition in polycrystalline, Pd-capped YHx switchable mirrors upon hydrogenation is investigated. Using the accompanying optical transition, we study switching of matrix-like samples with many (∼200) combinations of Pd and Y layer thicknesses. We find that: (i) With increasing Y thickness dY, the switching time τ increases for any constant Pd thickness dPd. (ii) With increasing dPd, there are three regimes. In regime I, it is impossible to switch a device. This can mainly be related to Pd-Y compound formation consuming all Pd within the UHV system, followed by surface oxidation in air. In regimes II and III switching is possible, but only in regime III does Pd form a closed cap layer. The Pd thickness needed for a closed cap layer depends on dY. (iii) An oxide buffer layer hinders Pd-Y interdiffusion, so that a thinner Pd cap layer is needed for switching than in the case without buffer layer. This is interesting for potential applications since it yields a higher optical transmission in the open state of the device.
UR - http://www.scopus.com/inward/record.url?scp=0000133708&partnerID=8YFLogxK
U2 - 10.1063/1.371660
DO - 10.1063/1.371660
M3 - Article
AN - SCOPUS:0000133708
SN - 0021-8979
VL - 86
SP - 6107
EP - 6119
JO - Journal of Applied Physics
JF - Journal of Applied Physics
IS - 11
ER -