Symmetric bidirectional silicon-controlled rectifier

The present invention discloses a symmetric bidirectional silicon-controlled rectifier, which comprises: a substrate; a buried layer formed on the substrate; a first well, a middle region and a second well, which are sequentially formed on the buried layer side-by-side; a first semiconductor area and a second semiconductor area both formed inside the first well; a third semiconductor area formed in a junction between the first well and the middle region, wherein a first gate is formed over a region between the second and third semiconductor areas; a fourth semiconductor area and a fifth semiconductor area both formed inside the second well; a sixth semiconductor area formed in a junction between the second well and the middle region, wherein a second gate is formed over a region between the fifth and sixth semiconductor areas.