US 12,274,025 B2
Method for fabricating MEMS-based cooling systems
Suryaprakash Ganti, Los Altos, CA (US); Brian James Gally, Los Gatos, CA (US); Ming Tung, Fremont, CA (US); Seshagiri Rao Madhavapeddy, La Jolla, CA (US); Vikram Mukundan, San Ramon, CA (US); Ananth Saran Yalamarthy, Stanford, CA (US); and Leonard Eugene Fennell, San Jose, CA (US)
Assigned to Frore Systems Inc., San Jose, CA (US)
Filed by Frore Systems Inc., San Jose, CA (US)
Filed on Sep. 7, 2021, as Appl. No. 17/468,151.
Claims priority of provisional application 63/079,460, filed on Sep. 16, 2020.
Prior Publication US 2022/0087064 A1, Mar. 17, 2022
Int. Cl. B23P 15/26 (2006.01); H05K 7/20 (2006.01); F04B 43/04 (2006.01); H01L 23/473 (2006.01)
CPC H05K 7/20272 (2013.01) [B23P 15/26 (2013.01); F04B 43/046 (2013.01); H01L 23/473 (2013.01)] 5 Claims
OG exemplary drawing
 
1. A method for providing a cooling system, the method comprising:
providing a plurality of sheets, each of the plurality of sheets including at least one structure for a corresponding level of a plurality of levels in each cooling cell of a plurality of cooling cells, wherein the plurality of levels includes a first level, a second level, and a third level, and wherein the providing of the plurality of sheets further includes:
providing a top plate sheet, the top plate sheet including at least one vent therein for each cooling cell of the plurality of cooling cells, wherein the top plate sheet corresponds with the first level;
providing an orifice plate sheet having a plurality of orifices therein, wherein the orifice plate sheet corresponds with the second level;
providing an active element sheet including a cooling element for each cooling cell of the plurality of cooling cells, the cooling element having a central region and a perimeter, at least a portion of the perimeter being free to undergo vibrational motion, wherein the cooling element having a first side and a second side, the cooling element being configured to undergo the vibrational motion to drive fluid from the first side to the second side to flow across a surface of a heat-generating structure to cool the heat-generating structure, wherein the active element sheet corresponds with the third level, wherein the providing of the active element sheet comprises:
selectively etching a substrate to provide a plurality of regions having a plurality of heights, the substrate including at least one of stainless steel, an Al alloy, and a Ti alloy;
providing a piezoelectric layer on a portion of the substrate;
providing an insulating barrier on the substrate;
providing a bottom electrode on the insulating barrier, the piezoelectric layer residing on the bottom electrode; and
connecting the bottom electrode to the substrate, the connecting the bottom electrode include a process selected from providing a jumper between the bottom electrode and the substrate and providing at least one via in the insulating barrier prior to the providing the bottom electrode, wherein the jumper corresponds to a metal layer;
aligning the plurality of sheets;
attaching the plurality of sheets to form a laminate, the laminate including the plurality of cooling cells; and
separating the laminate into a plurality of sections, each of the plurality of sections including at least one cooling cell of the plurality of cooling cells.