| 释义 |
PIN (Positive Intrinsic Negative) A type of diode used as a light detector in optical transmission sys- tems. A PIN comprises three layers of semiconducting material in the forward current-carrying direction. The first layer is chemically doped, i.e., infused with impurities, to create a positive ( p) electromagnetic region.The second layer is either undoped or lightly doped to retain its intrinsic ( i) properties and, therefore, is neither strongly positive nor strongly negative. The third layer is doped to create a negative ( n) electromagnetic region. So, the diode structure is Positive, Intrinsic, and Negative, or PIN. A PIN generates a single electron from each photon received and, therefore, does not provide a significant gain, or 74570c16.qxd 9/11/07 12:27 PM Page 376 |