abstract
| - Diodes are the basic building blocks for most semiconductor devices. They are part of the bipolar family of devices. Diodes consist of two semiconductor materials, one doped with a deficiency of electrons called p-type material, and the other side is doped with an extra abundancy of electrons called n-type material. A process known as doping the material is what makes some parts of the diode p-type and the other parts n-type. While growing the semiconductor crystal, a small amount of arsenic or phosphorus can be mixed in with the process and dope the material. To change the type of material from p to n type, one can add some n-type chemicals to swamp out the p-type materials already in the 'substrate'. When you get done with the making of a diode, you have two types of material in direct contact with one another - this is called an abrupt pn-junction. The p-side is called the anode and collects the electrons emitted from the cathode, the n-side. Benjamin Franklin was an early experimenter with electrical devices and setup the convention for current flow. All electrical engineers around the world use his convention for current flow and it states that current flows from the positive terminal of the battery through the circuit returning back to the negative terminal. The fact is that electrons flow the opposite way. Concern is not over the direction of the electron's flow(which only makes up half of the particles participating in electricity), but the direction of the charge. Current flows in the diode from the P terminal to the N terminal, NOT the other way around (even though electrons flow the opposite way). Essentially, its the same as a one-way check valve for electricity!
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