Title :
Aluminum-Germanium eutectic bonding for 3D integration
Author :
Crnogorac, Filip ; Birringer, Ryan ; Dauskardt, Reinhold ; Pease, Fabian
Author_Institution :
Dept. of Electr. Eng., Stanford Univ., Stanford, CA, USA
Abstract :
Low-temperature aluminum-germanium (Al-Ge) eutectic bonding has been investigated for monolithic three-dimensional integrated circuits (3DIC) applications. Successful bonds using Al-Ge bilayer films as thin as 157 nm were achieved at temperatures as low as 435degC, when applying 200 kPa down-pressure for 30 minutes. The liquid phase of the eutectic composition ensured a seamless and void-free bond. The fracture energy of the Al-Ge bond (630 nm thick) was measured to be Gc = 50.5 plusmn 12.7 J/m2, using double cantilever beam thin-film adhesion measurement technique. An array of silicon islands was attached onto an amorphous SiO2 wafer using low-temperature Al-Ge bonding. These islands could be used to form devices on upper layers of monolithically integrated 3DICs.
Keywords :
aluminium; germanium; integrated circuit bonding; monolithic integrated circuits; silicon compounds; thin films; Al-Ge; SiO2; double cantilever beam thin-film adhesion measurement technique; low-temperature eutectic bonding; monolithic three-dimensional integrated circuits; pressure 200 kPa; size 150 nm; size 630 nm; temperature 435 degC; time 30 min; Adhesives; Bonding; Energy measurement; Measurement techniques; Silicon; Structural beams; Temperature; Thickness measurement; Three-dimensional integrated circuits; Transistors; 3DIC; Al-Ge eutectic; monolithic integration; wafer bonding;
Conference_Titel :
3D System Integration, 2009. 3DIC 2009. IEEE International Conference on
Conference_Location :
San Francisco, CA
Print_ISBN :
978-1-4244-4511-0
Electronic_ISBN :
978-1-4244-4512-7
DOI :
10.1109/3DIC.2009.5306531
