With the rise of smartphones, they are no longer as small and
thick as we used to see. Nowadays, the sound quality and size of
mobile phones are increasingly valued. So silicon microphones
also appear in our field of vision, so what material is silicon
microphones made of? What is its working principle?
A silicon microphone is a miniature sensor. Pressure is mainly
generated by changes in sound, and then through pressure
gradients, the diaphragm of the silicon microphone is deformed,
causing a change in the capacitance value between the diaphragm
and the silicon backplane. The capacitance value will change as
the capacitance voltage is converted into changes in the
circuit, and then amplified by the circuit. The voltage is
amplified by the sensor to form a voltage signal.
To achieve this goal, the silicon microphone wants to use a high
impedance resistor as the bias voltage for the MEMS. With the
help of resistance, a fixed charge is generated on the sensor,
and the output voltage is proportional to the shape of the
membrane. The deformation of the membrane is closely related to
its stiffness, which is inversely proportional, meaning that the
lower the stiffness, the greater the deformation. The output
voltage is inversely proportional to the air gap, and the
smaller the air gap, the higher the sensitivity.
Compared with ordinary microphones, silicon microphones have the
following advantages: 1. They can directly convert sound into
electrical signals; 2. Has high sensitivity; 3. Has the
characteristics of resistance to falls and impacts; 4. Small in
size and light in weight; 5. Can be welded at high temperatures.
Smartphones generally integrate more than 8 silicon microphones,
which can accurately locate the sound position and achieve clear
voice transmission in noisy environments.
Silicon microphones have a wide range of applications. In the
field of biomedical equipment, it can be applied to: hearing
aids, electronic ears; In the computer communication industry,
it can be used for: mobile phones, digital cameras, hands-free
phones, laptops, etc. With the booming development of the
electronics industry and the advancement of manufacturing
processes and packaging technology, the design products of
silicon microphones are becoming more and more functional. The
advantages are short, small, lightweight, thin, energy-saving,
and cheap.
The main material of silicon microphones is silicon
semiconductors, which have good effects on analog amplification
circuits. This material is very suitable for use in light, thin,
and short devices. Nowadays, more and more silicon microphones
are being used in smart devices. I believe everyone now has a
partial understanding of the working principle and materials of
microphones. If you want to learn more, you can consult
professionals.
