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sunshine111
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I want to know the basic principle of working for quartz crystal microbalance, how it is used to measure the thickness of the film?And why it can work at room temp (with water cooling) and at higher temp say 65deg ??
vk6kro said:He is also asking about the temperature coefficient of quartz crystals.
He hasn't said what the machine is doing so that leaves room to guess.
You could measure the frequency at two temperatures at the extreme range of the device's range and then assume a linear frequency shift in between those readings.
Then you know the unloaded frequency and can work out the shift in frequency from the measured frequency when a load is put on.
It would be good if he told us this stuff, but even making a bad guess brings a reply and explains a little more of the situation.
Matlab, do you feel the coating is put on the crystal that is oscillating or is it put on something else which then adds weight to the crystal and affects its oscillation? Seems like the second one would be less destructive.
A quartz crystal microbalance (QCM) is a scientific instrument used to measure mass changes on the surface of a quartz crystal. It works by measuring the changes in frequency of a quartz crystal resonator caused by the addition or removal of material on its surface.
A quartz crystal microbalance consists of a thin quartz crystal coated with a conductive material and placed in a chamber filled with a gas or liquid. As material is added or removed from the crystal surface, the mass changes cause a shift in the crystal's resonant frequency, which is measured by an electronic circuit and converted into a mass reading.
QCMs are commonly used in research and industrial settings for studying surface phenomena such as adsorption, desorption, and film growth. They are also used in biosensors for detecting biomolecular interactions and in the development of new materials for various applications.
QCMs offer high sensitivity, fast response time, and the ability to measure mass changes in real time without the need for labeling or optical detection. They are also relatively small and easy to use, making them a valuable tool for a wide range of scientific and industrial applications.
While QCMs are a powerful analytical tool, they do have some limitations. For example, they are sensitive to temperature changes and require a stable environment for accurate measurements. They also have a limited dynamic range and may not be suitable for studying very large or highly viscous samples.