Direct Al-Al contact in silicon-Pyrex7740 anodic bonding for hermetic package and electrical interconnecting

Author(s):  
Xiaoshan Zheng ◽  
Xin Yan ◽  
Zijun Song ◽  
Haisheng San ◽  
Xuyuan Chen
Micromachines ◽  
2021 ◽  
Vol 12 (4) ◽  
pp. 382
Author(s):  
Chao Xiang ◽  
Yulan Lu ◽  
Chao Cheng ◽  
Junbo Wang ◽  
Deyong Chen ◽  
...  

This paper presents a resonant pressure microsensor with a wide range of pressure measurements. The developed microsensor is mainly composed of a silicon-on-insulator (SOI) wafer to form pressure-sensing elements, and a silicon-on-glass (SOG) cap to form vacuum encapsulation. To realize a wide range of pressure measurements, silicon islands were deployed on the device layer of the SOI wafer to enhance equivalent stiffness and structural stability of the pressure-sensitive diaphragm. Moreover, a cylindrical vacuum cavity was deployed on the SOG cap with the purpose to decrease the stresses generated during the silicon-to-glass contact during pressure measurements. The fabrication processes mainly contained photolithography, deep reactive ion etching (DRIE), chemical mechanical planarization (CMP) and anodic bonding. According to the characterization experiments, the quality factors of the resonators were higher than 15,000 with pressure sensitivities of 0.51 Hz/kPa (resonator I), −1.75 Hz/kPa (resonator II) and temperature coefficients of frequency of 1.92 Hz/°C (resonator I), 1.98 Hz/°C (resonator II). Following temperature compensation, the fitting error of the microsensor was within the range of 0.006% FS and the measurement accuracy was as high as 0.017% FS in the pressure range of 200 ~ 7000 kPa and the temperature range of −40 °C to 80 °C.


2021 ◽  
pp. 257-278
Author(s):  
Masayoshi Esashi
Keyword(s):  

2021 ◽  
Vol 13 (3) ◽  
pp. 168781402110077
Author(s):  
Chao Du ◽  
Cuirong Liu ◽  
Xu Yin ◽  
Haocheng Zhao

Herein, we synthesized a new polyethylene glycol (PEG)-based solid polymer electrolyte containing a rare earth oxide, CeO2, using mechanical metallurgy to prepare an encapsulation bonding material for MEMS. The effects of CeO2 content (0–15 wt.%) on the anodic bonding properties of the composites were investigated. Samples were analyzed and characterized by alternating current impedance spectroscopy, X-ray diffraction, scanning electron microscopy, differential scanning calorimetry, tensile strength tests, and anodic bonding experiments. CeO2 reduced the crystallinity of the material, promoted ion migration, increased the conductivity, increased the peak current of the bonding process, and increased the tensile strength. The maximum bonding efficiency and optimal bonding layer were obtained at 8 wt% CeO2. This study expands the applications of solid polymer electrolytes as encapsulation bonding materials.


2011 ◽  
Vol 95 (11) ◽  
pp. 3001-3008 ◽  
Author(s):  
Matthias M. Koebel ◽  
Nancy El Hawi ◽  
Jia Lu ◽  
Felix Gattiker ◽  
Jürg Neuenschwander

Author(s):  
Navdeep S. Dhillon ◽  
Jim C. Cheng ◽  
Albert P. Pisano

A novel two-port thermal flux method is implemented for degassing a microscale loop heat pipe (mLHP) and charging it with a working fluid. The mLHP is fabricated on a silicon wafer using standard MEMS micro-fabrication techniques, and capped by a Pyrex wafer, using anodic bonding. For these devices, small volumes and large capillary forces render conventional vacuum pump-based methods quite impractical. Instead, we employ thermally generated pressure gradients to purge non-condensible gases from the device, by vapor convection. Three different, high-temperature-compatible, MEMS device packaging techniques have been studied and implemented, in order to evaluate their effectiveness and reliability. The first approach uses O-rings in a mechanically sealed plastic package. The second approach uses an aluminum double compression fitting assembly for alignment, and soldering for establishing the chip-to-tube interconnects. The third approach uses a high temperature epoxy to hermetically embed the device in a machined plastic base package. Using water as the working fluid, degassing and filling experiments are conducted to verify the effectiveness of the thermal flux method.


2003 ◽  
Vol 13 (6) ◽  
pp. 845-852 ◽  
Author(s):  
K Schj lberg-Henriksen ◽  
G U Jensen ◽  
A Hanneborg ◽  
H Jakobsen
Keyword(s):  

2002 ◽  
Vol 729 ◽  
Author(s):  
Lauren E. S. Rohwer ◽  
Andrew D. Oliver ◽  
Melissa V. Collins

AbstractA wafer level packaging technique that involves anodic bonding of Pyrex wafers to released surface micromachined wafers is demonstrated. Besides providing a hermetic seal, this technique allows full wafer release, provides protection during die separation, and offers the possibility of integration with optoelectronic devices. Anodic bonding was performed under applied voltages up to 1000 V, and temperatures ranging from 280 to 400°C under vacuum (10-4Torr). The quality of the bonded interfaces was evaluated using shear strength testing and leak testing. The shear strength of Pyrex-to-polysilicon and aluminum bonds was ∼10-15 MPa. The functionality of surface micromachined polysilicon devices was tested before and after anodic bonding. 100% of thermal actuators, 94% of torsional ratcheting actuators, and 70% of microengines functioned after bonding. The 70% yield was calculated from a test sample of 25 devices.


Sign in / Sign up

Export Citation Format

Share Document