Crystal diode rectifier

Considerable interest in the sohd-state physics of sihcon carbide, that is, the relation between its semiconductor characteristics and crystal growth, has resulted from the expectation that SiC would be useflil as a high temperature-resistant semiconductor in devices such as point-contact diodes (148), rectifiers (149), and transistors (150,151) for use at temperatures above those where sihcon or germanium metals fail (see Semiconductors). 

Ni or Au coated rounds (W). They serve as supports for silicon single-crystal plates used in transistors, diodes, thyristors, and rectifiers. 

It was of academic interest, ever since the discovery of the transistor, to see whether organic molecules could function as bulk pn rectifiers (diodes), or as npn transistors. This would occur if a film or crystal of an organic electron donor were brought in contact with that of an organic electron acceptor. This was indeed verified in the 1960 s[38]. 

In 1907, H. J. Round reported that light could be emitted by passing current through a crystal rectifier junction under the right circumstances. This was the ancestor of the modern LED, though the term diode had not yet been invented. Though research... 

This radio receiver is a "crystal set," with a "diode detector." The functions of each part will be described later in this chapter. The crystal in this case is the silicon inside the diode. However, as many readers already know, historically it used to be a single crystal of the mineral galena (lead sulfide), which is a natural semiconductor. It had to be contacted with a sharp metal wire. Surprisingly, the sharp point forces a small region of the N-type galena to become P-type, making a special kind of "point contact" PN junction. At any rate, old style or new, the detector is a rectifier. (It could be a three-wire transistor, with a battery, etc.)... 

The operation of solid-state microelectronic devices largely depends on specific electrical responses occurring at the interface between materials of different nature. A representative example for this statement is the rectifying property of the metal-semiconductor contact, which has been identified as early as the end of the nineteenth century (the semiconductor properties of galena were identified by Karl Ferdinand Braun in 1874 32 years later, Greenleaf Whittier Pickard patented a crystal radio receiver [1], which used a crystal detector that was actually a metal-semiconductor diode made of galena). As a consequence, the performance of these devices critically depends on the quality and reliability of their interfaces. Organic electronic devices do not escape this universal rule. 

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