[17a-B1-1~7] 13.4 Si processing /Si based thin film / MEMS / Equipment technology

9:45 AM - 10:00 AM JST(12:45 AM - 1:00 AM UTC)Presentation by Applicant for JSAP Young Scientists Presentation Award

[17a-B1-4] Effect of Perforated Proof-Mass Hole Size on Brownian Noise B_N of Gold Single-Axis MEMS Accelerometer for Micro-g Level Sensing

〇(B)Torauto Yamada¹, Kisuke Miyado¹, Devi Srujana Tenneti¹, Chihaya Mukaide¹, Katsuyuki Machida¹, Tso-Fu Mark Chang¹, Tomoyuki Kurioka¹, Masato Sone¹, Yoshihiro Miyake¹, Hiroyuki Ito¹ (1.Tokyo Tech.)

Keywords:

MEMS acclerometer,Brownian noise,hole size

This paper describes the relationship between the proof-mass hole size of Au proof-mass single-axis MEMS accelerometers and Brownian noise BN, which is a determinant of high sensitivity. For micro-g (1g = 9.8m/s²) level sensing, we need to reduce the Brownian noise B_N of a MEMS accelerometer to less than 1.0 μg/√Hz. We have developed a highly sensitive MEMS accelerometer with a gold perforated proof-mass. The relationship between the hole size and device performance has not been reported previously, and this relationship is the first to be investigated using the damping coefficient model proposed by our group. In this paper, we focus on the hole size, which is related to the ease of MEMS process. As a result, the hole size dependence of B_N is clarified. We design and fabricate the gold single-axis MEMS accelerometer with 40μm hole to verify its validity. The ring-down tests using a laser Doppler vibrometer to estimate the B_N is carried out. Experimental result shows that the value of B_N is 300 ng/√Hz, which fulfills the target value of 1.0μg/√Hz. In conclusion, it is confirmed the MEMS accelerometer with 40µm hole is suitable in terms of both MEMS process and micro-g level sensing.