Batteries
Early in the history of electrical science, laboratory physicists found that when metals came into contact with certain chemical solutions, voltages appeared between the pieces of metal. These were the first electrochemical cells. More ...
Integrated Circuit Manufacturing Etching
photolithography is the process of transferring patterns to photoresist covering the surface of a semiconductor wafer. To produce circuit features, these resist patterns must be transferred into the underlying layers of the device. Pattern transfer is accomplished by an etching process that selectively removes unmasked portions of a layer. More ...
Phase shift in AC Circuits
In an AC circuit with a capacitor or an inductor there is a phase shift between voltage and current. In this article you learn how to calculate the amount of that phase shift. More ...
Lithium Ion Battery Chemistry
Lithium-ion (Li-ion) batteries are one of the most common portable power sources used today. Impurities in the materials used to construct a lithium battery can cause it to overheat. More ...
Lead-Acid Battery Chemistry
As a lead-acid battery is repeatedly recharged, sulfation will build-up on the plates and the battery will begin to loose its capacity to restore to a full charge and eventually must be replaced. More ...
Integrated Circuit Manufacturing E-Beam Lithography
Optical lithography high resolution, at low cost, but it has limitations. Electron-beam lithography uses an electron gun to generate a beam of electrons to produce submicrometer resist geometries without a mask. More ...
Integrated Circuit Manufacturing Packaging
Before ICs can be put to their intended use they must be packaged. The package is responsible for interconnecting, powering, cooling, and protecting the IC. More ...
Integrated Circuit Manufacturing Bipolar Technology
Bipolar junction transistors (BJTs) are still used in integrated circuits (ICs) for switching, signal amplification, and radio-frequency circuits because they are faster than CMOS transistors. More ...
Electric Fields and Static Electricity
Static electricity is a phenomenon caused by a buildup of unbalanced electric charge that is not moving. We are all familiar with the static electric charge caused by dragging our feet across a carpet and then the sudden static discharge caused by grabbing a door knob. More ...
Integrated Circuit Manufacturing Deposition
Many different types of thin films are used to manufacture integrated circuits, including thermal oxides, dielectric layers, epitaxial layers, polycrystalline silicon, and metal films. This article addresses two techniques for depositing such films. More ...
Inductors in Series and Parallel
With inductors connected in series, the total inductance is the sum of the inductances of the individual inductors With inductors in parallel, the reciprocal of the equivalent inductance is the sum of the reciprocals of the inductors connected in parallel. More ...
Electromagnetic Devices
Electromagnetic devices work based on the relationship between electrical current and a magnetic field. They are used to control valves, cooling and heating systems, relays, and electric motors. More ...
Integrated Circuits
An integrated circuit (IC) is a thin rectangular piece of semiconductor upon which, using a photographic process, thousands of electronic components, and the conducting paths to connect them, are printed. The types circuits that can be etched into a semiconductor chip range from amplifiers to logic gates and even microprocessors with millions of transistors. More ...
Common Emitter Configuration Transistor Biasing
To design a common emitter amplifier circuit, use a voltage divider with resistors selected to set the base voltage at the center of the transistor's linear region. Then, through a DC blocking capacitor, apply a waveform to the transistor's base. More ...
