SemiConductor type strain gauge

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Semiconductor type strain gauge

In this type of strain gauge we use doped silicon or  germanium as a sensing element.
When we apply stress to this type of material its Resistance is changed, by measuring the  resistance change we can  measure the stress applied on this material.

Gauge factor of this type of strain gauge is well around 100.

  • Unlike other strain gauges, semiconductor strain gages are based upon the piezoresistive effects of silicon or germanium and measure the change in resistance with stress as opposed to strain.
  • The semiconductor bonded strain gage is a wafer with the resistance element diffused into a substrate of silicon.
  • No backing is provided for the wafer element and bonding it to the strained surface needs extra care since only a thin layer of epoxy is used to attach it.
  • Size of a semiconductor strain gauge is much smaller and the cost much lower than for a metallic foil sensor.

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