Editing Piezoelectricity (section)

===III–V and II–VI semiconductors===
A piezoelectric potential can be created in any bulk or nanostructured semiconductor crystal having non central symmetry, such as the [[List of semiconductor materials#Types of semiconductor materials|Group]] [[Boron group|III]]–[[Nitrogen group|V]] and [[Group 12 element|II]]–[[Chalcogen|VI]] materials, due to polarization of ions under applied stress and strain. This property is common to both the [[zincblende]] and [[wurtzite]] crystal structures. To first order, there is only one independent piezoelectric coefficient in [[zincblende]], called e<sub>14</sub>, coupled to shear components of the strain. In [[wurtzite]], there are instead three independent piezoelectric coefficients: ''e''<sub>31</sub>, ''e''<sub>33</sub> and ''e''<sub>15</sub>.
The semiconductors where the strongest piezoelectricity is observed are those commonly found in the [[wurtzite]] structure, i.e. [[GaN]], [[InN]], [[AlN]] and [[ZnO]] (see [[piezotronics]]).

Since 2006, there have also been a number of reports of strong [[non linear piezoelectric effects in polar semiconductors]].<ref>{{cite conference |title=A Review of Non Linear Piezoelectricity in Semiconductors |first=Max |last=Migliorato |conference=AIP Conference Proceedings|volume=1590 |issue=N/A |pages=32–41 |doi=10.1063/1.4870192|display-authors=etal|series=AIP Conference Proceedings |year=2014 |bibcode=2014AIPC.1590...32M |doi-access=free }}</ref>
Such effects are generally recognized to be at least important if not of the same order of magnitude as the first order approximation.