Number of semiconductor layers on SCR are
Correct answer: 3. Four
The number of semiconductor layers on SCR are Four.
Shockley diodes are curious devices, but rather limited in application. Their usefulness may be expanded, however, by equipping them with another means of latching. In doing so, each becomes true amplifying devices (if only in an on/off mode), and we refer to these as silicon-controlled rectifiers, or SCRs. Continue reading about Working and construction of SCR here