abstract |
A material 4 having a predetermined coefficient of spatial expansion is deposited on the porous substrate 10 to form a fluid impermeable thin film 20. The material 4 is deposited and then oxidized and expanded to form a non-porous film on the upper surface of the porous substrate 10. The particle boundary 6 of the non-porous membrane is recombined to form the continuous thin film 20 on the porous substrate 10. |