Development of Directional MEMS Microphone Single Module for High Directivity and SNR

Micro-Electro-Mechanical Systems Microphones: A Brief Review Emphasizing Recent Advances in Audible Spectrum Applications

“…In some circumstances, slits can occur in the diaphragm structure if the corrugations are made deeper, as per the findings of Yoo et al A membrane with slit edges significantly increases the compliance of the membrane [ 23 ]. The optical image in Figure 4 .…”

“…For more specific applications, such as in-vehicle noise reduction, directional signal selection can also be achieved at the packaging level. As illustrated in Figure 14 a, Yoo et al [ 23 ] presented a unidirectional microphone that enables the suppression of noise signals from undesired directions. As illustrated in Figure 14 b, The directional characteristic of the microphone is realized by attaching a porous SU-8 filter to facilitate a delay in one of the two acoustic ports on the package.…”

“… Measurements and photos of structure deformation of the microphone diaphragm after deposition process (Reprinted with permission from Ref. [ 23 ]). …”

“… Optical images of the membrane with or without slit structure (Reprinted with permission from Ref. [ 23 ]). …”

Highly Sensitive Low-Frequency-Detectable Acoustic Sensor Using a Piezoresistive Cantilever for Health Monitoring Applications

“…Microphones, which convert sound waves to electrical signals, are indispensable in various applications, such as consumer electronics [1][2][3][4][5] , automobiles 6 , hearing aid devices 7,8 , wearable health monitoring [9][10][11][12][13][14][15][16][17][18][19] , photoacoustic-based gas sensing [20][21][22][23][24][25] , and the monitoring of natural disasters, such as volcanic eruptions [26][27][28] , debris flow 29 , and earthquakes 30 . Two widely used types of microphones exist, traditional electret condenser and microelectromechanical systems (MEMS)-based microphones.…”