TY - GEN
T1 - Improved Vacuum Level of Silicon-Migration-Sealed Cavity by Hydrogen Diffusion Annealing for Wafer-Level Packaging for Mems
AU - Suzuki, Hirotaka
AU - Suzuki, Yukio
AU - Kanamori, Yoshiaki
AU - Tanaka, Shuji
N1 - Funding Information:
The part of this paper is based on results obtained from a project, JPNP 19005, commissioned by the New Energy and Industrial Technology Development Organization (NEDO).?Almost all of the manufacturing processes were carried out at the Micro System Integration Center, Tohoku University, partly supported by the Nanotechnology Platform Japan of the Ministry of Education, Culture, Sports, Science and Technology. We would like to express our gratitude to Mr. Honda of Sony Semiconductor Manufacturing Corporation for his advanced technical support in etching process, and Mr. Maejima of ESCO, Ltd for his precise advice in TDS evaluation. We would like to take this opportunity to thank them.
Publisher Copyright:
© 2022 IEEE.
PY - 2022
Y1 - 2022
N2 - A sealing vacuum level better than 10 Pa was achieved by Silicon Migration Seal (SMS) technology without film deposition or using a getter for the first time. SMS utilizes silicon reflow phenomena in hydrogen at high temperature (>1000°C) to close release holes. In this study, we confirmed the sealing vacuum level using silicon diaphragms fabricated in a device wafer. And the samples were placed in a vacuum chamber with a diaphragm pressure gauge to evaluate vacuum level of the sealed cavity. The vacuum level got better than the detection limit of about 10 Pa after 35 hours annealing in nitrogen, during which hydrogen diffused out. In addition, we did thermal desorption spectroscopy (TDS) to analyze residual gas in a sealed cavity, which was almost hydrogen as expected. SMS is promising for inexpensive high vacuum encapsulation of gyroscopes, timing resonators etc.
AB - A sealing vacuum level better than 10 Pa was achieved by Silicon Migration Seal (SMS) technology without film deposition or using a getter for the first time. SMS utilizes silicon reflow phenomena in hydrogen at high temperature (>1000°C) to close release holes. In this study, we confirmed the sealing vacuum level using silicon diaphragms fabricated in a device wafer. And the samples were placed in a vacuum chamber with a diaphragm pressure gauge to evaluate vacuum level of the sealed cavity. The vacuum level got better than the detection limit of about 10 Pa after 35 hours annealing in nitrogen, during which hydrogen diffused out. In addition, we did thermal desorption spectroscopy (TDS) to analyze residual gas in a sealed cavity, which was almost hydrogen as expected. SMS is promising for inexpensive high vacuum encapsulation of gyroscopes, timing resonators etc.
KW - Epi-Seal
KW - Hydrogen anneal
KW - Silicon migration
KW - Vacuum sealing
KW - Wafer-level packaging
KW - thermal desorption spectroscopy
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U2 - 10.1109/MEMS51670.2022.9699602
DO - 10.1109/MEMS51670.2022.9699602
M3 - Conference contribution
AN - SCOPUS:85126392053
T3 - IEEE Symposium on Mass Storage Systems and Technologies
SP - 565
EP - 568
BT - 35th IEEE International Conference on Micro Electro Mechanical Systems Conference, MEMS 2022
PB - IEEE Computer Society
T2 - 35th IEEE International Conference on Micro Electro Mechanical Systems Conference, MEMS 2022
Y2 - 9 January 2022 through 13 January 2022
ER -