Micro-electro-mechanical valves and pumps and methods of fabricating same

A micro-pump having an inlet and an outlet, said micro-pump comprising:

• a first lower chamber having a bottom wall and sidewalls, a second lower chamber having a bottom wall and sidewalls, a third lower chamber having a bottom wall and sidewalls, and an upper chamber having a top wall and sidewalls, a first region of a bottom of said upper chamber separated from a top of said first lower chamber by a porous, flexible and electrically conductive first mat of nano-fibers, a second region of said bottom of said upper chamber separated from a top of said second lower chamber by a non-porous, flexible and electrically conductive second mat of nano-fibers, and a third region of said bottom of said upper chamber separated from a top of said third lower chamber by a porous, flexible and electrically conductive third mat of nano-fibers, said first, second and third mats of nano-fibers electrically isolated from each other;
• openings in said top wall of said upper chamber aligned only over said first and third mats of nano-fibers, a first opening of said openings aligned over said first mat of nano- fibers and a second opening of said openings aligned over said third mat of nano-fibers;
• an impervious first valve seal on said first mat of nano-fibers, said first valve seal below and self-aligned to said first opening;
• an impervious second valve seal on said third mat of nano-fibers, said second valve seal below and self-aligned to said second opening;
• a first electrically conductive plate under said bottom walls of said first, second and third lower chambers and a second electrically conductive plate above said top wall of said lower chamber;
• a first electrical contact to said first mat of nano-fibers;
• a second electrical contact to said second mat of nano-fibers;
• a third electrical contact to said third mat of nano-fibers;
• a fourth electrical contact to said first conductive plate;
• and
• a fifth electrical contact to said second conductive plate.

A method of fabricating a micro-valve having an inlet and an outlet, said method comprising:

• on a substrate, forming a lower chamber having a bottom wall and sidewalls and forming an upper chamber having a top wall and sidewalls, a bottom of said upper chamber separated from a top of said lower chamber by a porous, flexible and electrically conductive mat of nano-fibers;
• forming an opening in said top wall of said upper chamber, said opening open to said upper chamber;
• forming an impervious valve seal on said mat of nano-fibers, said valve seat below and self-aligned to said opening;
• forming an electrically conductive plate under and electrically isolated from said bottom wall of said lower chamber, said first conductive plate formed on an insulating layer formed on said substrate;
• forming a first electrical contact to said conductive plate;
• forming a second electrical contact to said mat of nano-fibers;
• forming an additional conductive plate on top of said upper chamber;
• forming a third electrical contact to said additional conductive plate;
• forming an additional opening into said bottom chamber, said inlet comprised of said additional opening and said outlet comprised of said opening;
• forming said lower chamber includes forming a first trench in a first dielectric layer formed on said first conductive plate, filling said first trench with a first sacrificial material and forming said porous mat of nano-fibers over said first sacrificial material followed by removing said first sacrificial material;
• and
• forming said upper chamber includes forming a second trench in a second dielectric layer formed on said mat of nano-fibers, filling said second trench with a second sacrificial material, forming a third dielectric layer on said second dielectric layer and said second sacrificial material, forming a second conductive layer on said third dielectric, forming a fourth dielectric layer on said second conductive layer and forming an opening though said fourth dielectric layer, said second conductive layer and said third dielectric layer to said second sacrificial material and removing said second sacrificial material.

A method of fabricating a micro-pump having an inlet and an outlet, said method comprising:

• forming a first lower chamber having a bottom wall and sidewalls, forming a second lower chamber having a bottom wall and sidewalls, forming a third lower chamber having a bottom wall and sidewalls and forming an chamber having a top wall and sidewalls, forming a porous, flexible and electrically conductive first mat of nano-fibers, said first mat of nano-fibers separating a first region of a bottom of an upper chamber from a top of said first lower chamber, forming a non-porous, flexible and electrically conductive second mat of nano-fibers, said second mat of nano-fibers separating a second region of said bottom of said upper chamber from a top of said second lower chamber and forming a porous, flexible and electrically conductive third mat of nano-fibers, said third mat of nano-fibers separating a third region of said bottom of said upper chamber from a top of said third lower chamber, said first, second and third mats of nano-fibers electrically isolated from each other;
• forming openings in said top wall of said upper chamber aligned only over said first and third mats of nano-fibers, a first opening of said openings aligned over said first mat of nano-fibers and a second opening of said openings aligned over said third mat of nano-fibers;
• forming an impervious first valve seal on said first mat of nano-fibers, said first valve seal below and self-aligned to said first opening;
• forming an impervious second valve seal on said third mat of nano-fibers, said second valve seal below and self-aligned to said second opening;
• forming a first electrically conductive plate under said bottom walls of said first, second and third lower chambers and a second electrically conductive plate above said top wall of said lower chamber;
• forming a first electrical contact to said first mat of nano-fibers;
• forming a second electrical contact to said second mat of nano-fibers;
• forming a third electrical contact to said third mat of nano-fibers;
• forming a fourth electrical contact to said first conductive plate;
• and
• forming a fifth electrical contact to said second conductive plate.