Title :
Low temperature wafer direct bonding
Author :
Tong, Qin-Yi ; Cha, Giho ; Gafiteanu, Roman ; Gösele, Ulrich
Author_Institution :
Wafer Bonding Lab., Duke Univ., Durham, NC, USA
fDate :
3/1/1994 12:00:00 AM
Abstract :
A pronounced increase of interface energy of room temperature bonded hydrophilic Si/Si, Si/SiO2, and SiO2/SiO 2 wafers after storage in air at room temperature, 150°C for 10-400 h has been observed. The increased number of OH groups due to a reaction between water and the strained oxide and/or silicon at the interface at temperatures below 110°C and the formation of stronger siloxane bonds above 110°C appear to be the main mechanisms responsible for the increase in the interface energy. After prolonged storage, interface bubbles are detectable by an infrared camera at the Si/Si bonding seam. Desorbed hydrocarbons as well as hydrogen generated by a reaction of water with silicon appear to be the major contents in the bubbles. Design guidelines for low temperature wafer direct bonding technology are proposed
Keywords :
bubbles in solids; silicon; silicon compounds; wafer bonding; 10 to 400 h; 110 C; 150 C; OH groups; Si-Si; Si-SiO2; Si/Si; Si/SiO2; SiO2-SiO2; SiO2/SiO2 wafers; bonding seam; bubbles; design guidelines; desorbed hydrocarbons; hydrophilic; infrared camera; interface bubbles; interface energy; low temperature wafer direct bonding; low temperature wafer direct bonding technology; room temperature bonded; storage; strained oxide; Annealing; Chemicals; Conducting materials; Infrared detectors; Microstructure; Plasma temperature; Silicon; Thermal stresses; Tin; Wafer bonding;
Journal_Title :
Microelectromechanical Systems, Journal of
