针尖的弹性系数

contact mode probe need low spring constant to allow cantilever defleted easily. it mean lower force on surface.

Tapping mode probe need high spring constant to allow resonant vibration easily.

If you use Tapping mode probe for contact mode operation, the speing constant will be too high and destroy tip or sample easily. But it is good for you to do mechanical lithography.

If you use Contact mode probe to do Tapping moder operation, the spring constant is too low and it will give you a lower resonant frequency. From experience, it is unstable.But Tapping in fluid operation must use low spring constant probe.

You can fo to web site below to see frequency effect.

http://www.tbcl.com.tw/Product/SPM/SPM.htm