US 12,136,605 B2
Layer structures for making direct metal-to-metal bonds at low temperatures in microelectronics and method for forming the same
Guilian Gao, San Jose, CA (US); Gaius Gillman Fountain, Jr., Youngsville, NC (US); Laura Wills Mirkarimi, Sunol, CA (US); Rajesh Katkar, Milpitas, CA (US); Ilyas Mohammed, Santa Clara, CA (US); and Cyprian Emeka Uzoh, San Jose, CA (US)
Assigned to ADEIA SEMICONDUCTOR BONDING TECHNOLOGIES INC., San Jose, CA (US)
Filed by ADEIA SEMICONDUCTOR BONDING TECHNOLOGIES INC., San Jose, CA (US)
Filed on May 14, 2021, as Appl. No. 17/320,767.
Application 17/320,767 is a continuation of application No. 16/218,769, filed on Dec. 13, 2018, granted, now 11,011,494.
Claims priority of provisional application 62/725,801, filed on Aug. 31, 2018.
Prior Publication US 2022/0005784 A1, Jan. 6, 2022
Int. Cl. H01L 23/522 (2006.01); H01L 21/768 (2006.01); H01L 23/00 (2006.01)
CPC H01L 24/83 (2013.01) [H01L 21/76877 (2013.01); H01L 23/5226 (2013.01); H01L 24/09 (2013.01); H01L 24/16 (2013.01); H01L 24/32 (2013.01); H01L 24/81 (2013.01); H01L 2924/01029 (2013.01); H01L 2924/351 (2013.01)] 23 Claims
OG exemplary drawing
 
1. A method comprising:
providing a first trench or via in a first dielectric structure of a first substrate, wherein the first trench or via has a first width;
at least partially filling the first trench or via with one or more metals having a thickness of approximately 0.5-1.5 μm;
applying a second dielectric structure onto the first dielectric structure and onto the one or more metals;
forming a second trench or via in the second dielectric structure with a second width that is smaller than the first width;
at least partly filling the second trench or via with a first conductive material directly in contact with the one or more metals to form a conductive via;
applying a third dielectric structure onto the second dielectric structure and onto the first conductive material;
forming a third trench or via in the third dielectric structure with a third width that is larger than the second width but smaller than the first width;
at least partly filling the third trench or via with a second conductive material directly in contact with the first conductive material to form a metal pad over the conductive via, wherein only a single via connects to the metal pad, the single via comprising the conductive via; and
preparing the third dielectric structure and the metal pad to form a bonding surface for direct hybrid bonding to a second substrate.