Hefei Research Institute researched and invented polarized diodes

[ Instrument network instrument research and development ] Among the diode electronic components, a device with two electrodes only allows current to flow in a single direction, and many uses are for its rectification function. The varactor diode) is used as an electronic adjustable capacitor. The current directionality of most diodes is usually referred to as the "rectification" function. The more common function of diodes is to only allow current to pass in a single direction, and block in the reverse direction.

Recently, the Sheng Zhigao research team of the High Magnetic Field Center of the Hefei Research Institute of the Chinese Academy of Sciences collaborated with researchers from the Institute of Physics of the Chinese Academy of Sciences and the Ningbo Institute of Materials of the Chinese Academy of Sciences to invent a new type of electronic component-the "polarized diode", which may become the basic component of future electronic devices .

The research team introduced an appropriate amount of oxygen vacancies into the dielectric material strontium titanate (SrTiO3) by means of electrical fatigue. These oxygen vacancies and the surrounding electrons form "polarons", and these "polarons" can form electric polarization (P) under the action of an electric field. Then, by preparing a heterojunction composed of metallic titanium and fatigue strontium titanate, components with rectifying effect are constructed.

With the help of a strong magnetic field center steady state strong magnetic field experimental device (SHMFF) ultra-fast optical test system under superconducting magnets, the components have been studied in detail. The study found that when a negative electric field (-V) is applied to the component, the interface forms a very weak polarization P; when a positive electric field (+V) is applied to the component, the interface forms a very strong polarization P . This asymmetrical PV relationship indicates that the device has a polarized rectification effect, is a polarized diode, and may become a basic component of future electronic devices.

From the perspective of migration, electronics can be divided into two categories: cruise electronics and local electronics. For electronic components with cruising electrons as the carrier, there are two relationships between current (J) and voltage (V) under the action of an electric field. The first is a resistance element with a symmetric JV relationship; the second is a current diode with an asymmetric JV relationship (rectification effect). Current diodes are widely used in storage, computing, communication, display and other fields, and have become a more critical basic component in modern electronics. The situation is slightly different for electronic components that use local electronics as the carrier.

In addition, components such as capacitors with symmetrical polarization (P) and voltage (V) relationships have long been invented. As for the electronic components with asymmetric PV relationship (polarization rectification effect), there is no report so far. Therefore, if an asymmetric PV relationship can be found to form the rectification effect of polarization, then polarized diodes can be made, which will have very important potential applications in the fields of rectifiers, storage, and computing.

Finally, I learned that there are many types of diodes, which can be divided into germanium diodes (Ge tubes) and silicon diodes (Si tubes) according to the semiconductor materials used. According to its different uses, it can be divided into detection diodes, rectifier diodes, voltage regulator diodes, switching diodes, isolation diodes, Schottky diodes, light emitting diodes, silicon power switching diodes, rotating diodes, etc.

According to the die structure, it can be divided into point contact diodes, surface contact diodes and planar diodes. Point-contact diodes use a very thin metal wire to press on the surface of a clean semiconductor wafer, and pulse current is applied to make one end of the contact wire and the wafer firmly sintered together to form a "PN junction". Because it is a point contact, only a small current (not more than tens of milliamperes) is allowed to pass, and it is suitable for high-frequency and small-current circuits, such as radio detection. The "PN junction" area of ​​the surface contact diode is large, allowing a large current (a few amperes to tens of amperes) to pass, and it is mainly used in a "rectifier" circuit that converts alternating current into direct current. The planar diode is a special silicon diode, which can not only pass larger currents, but also has stable and reliable performance. It is mostly used in switches, pulses and high-frequency circuits.