The figure below shows a diagram of gallium arsenide (GaAs) MESFET (metal-semiconductor field-effect transistor). MESFET is nothing but a JFET fabricated in GaAs which employs a metal-semiconductor gate region (a Schottky diode). The device operates in essentially the same way as does a junction-gate FET, except that instead of a gate-channel on junction there is […]
Junction Characteristics Before describing the fabrication sequences for ICs, it will be useful to provide insight into the use of epitaxial structures for devices. A reverse-biased p-n junction can be considered to be a parallel-plate capacitor with the depletion region being the insulator or dielectric as shown in the figure below. The depletion or space-charge
To know about the different IC fabrication techniques, click on the link below. TAKE A LOOK : IC FABRICATION TECHNIQUES Metallization is the final step in the wafer processing sequence. Metallization is the process by which the components of IC’s are interconnected by aluminium conductor. This process produces a thin-film metal layer that will serve
To know about the different IC fabrication techniques, click on the link below. TAKE A LOOK : IC FABRICATION TECHNIQUES ION IMPLANTATION Ion Implantation is an alternative to a deposition diffusion and is used to produce a shallow surface region of dopant atoms deposited into a silicon wafer. This technology has made significant roads into
To know about the different IC fabrication techniques, click on the link below. TAKE A LOOK : IC FABRICATION TECHNIQUES Diffusion of Dopant Impurities The process of junction formation, that is transition from p to n type or vice versa, is typically accomplished by the process of diffusing the appropriate dopant impurities in a high
To know more about lithographic process and it’s basic types, click on the link below. TAKE A LOOK : IC FABRICATION TECHNIQUES TAKE A LOOK : PHOTOLITHOGRAPHY Electron-beam lithography provides better resolution then photolithography. This is possible because of small wavelength of the 10-50 KeV electrons. The resolution of electron-beam lithography system is not limited
To know more about lithographic process and it’s basic types, click on the link below. TAKE A LOOK : IC FABRICATION TECHNIQUES TAKE A LOOK : PHOTOLITHOGRAPHY The photolithography has its resolution limited by diffraction effects. To improve the resolution, therefore, the diffraction effects are reduced by reducing the wavelength. However, if the wavelength is
To know more about lithographic process and it’s basic types, click on the link below. TAKE A LOOK : IC FABRICATION TECHNIQUES TAKE A LOOK : PHOTOLITHOGRAPHY Ion-Beam Lithography Ion-beam lithography, when used to expose resist, provides higher resolution than that possible with an electron-beam because of less scattering. Also, resists are more sensitive to
To know more about the basics, click on the link below. TAKE A LOOK : IC FABRICATION TECHNIQUES When a sample of crystalline silicon is covered with silicon dioxide, the oxide-layer acts as a barrier to the diffusion of impurities, so that impurities separated from the surface of the silicon by a layer of oxide
To know the basics click on the following links TAKE A LOOK : IC FABRICATION TECHNIQUES TAKE A LOOK : SILICON SUBSTRATE PREPARATION TAKE A LOOK : CHEMICAL VAPOUR DEPOSITION (CVD) Utility of Thermal Oxidation The function of a layer of silicon dioxide (SiO2) on a chip is multipurpose. SiO2 plays an important role in
Chemical Vapor Deposition Process In this article, Chemical Vapor Deposition process is explained in detail. The epitaxial deposition, uses, and also the epitaxial growth of silicon is explained in detail. Doping and Autodoping, Epitaxial Reactors, Epitaxial Growth Process, their advantages and disadvantages are also explained. The different types of CVD reactors and their advantages and
Description. The circuit diagram of a simple capacitance meter using IC LM2917 is shown here. The LM2917 is a high gain monolithic frequency to voltage converter IC from National Semiconductors. Even though the main application of LM2917 is in tachometers, it can be also used for a variety of applications like this. Capacitance values from
Description. The circuit diagram shown here is of a simple DC power delay circuit that is based on an SCR. This circuit is a very handy one and can be employed in many applications. The working of this circuit is very simple. When the input power is applied the capacitor C2 charges through resistor R2
Silicon Substrate Preparation Process In this article the details on how a silicon substrate is prepared is given.We have structured the article into 5 sections as give below for easy and effective reading. 1. The silicon crystal growth 2. Electronic grade silicon production 3. Czochralski Crystal Growth Process 4. Wafer preparation 5. Wafer processing If
IC Fabrication Techniques In this article, the different processing techniques that are needed for IC , transistor and diode fabrication are listed. A small procedure of the fabrication process is also explained. In a monolithic IC, all the circuit components are fabricated into or top of a block of silicon which is referred to as
The “Universal Product Codeâ€, also known as UPC Bar Code can be found in almost all packages that you buy from department stores, grocery stores or any other stores. In this post we will discuss on where these codes come from and their actual use. You can also go through the topic Invention Story of
We have seen the use of facial recognition technology in many movies. A photo of the person to be identified will be obtained from some hidden camera. It will then be run in through the police database so as to find a match with their existing records. At last a match will be found and
Hi all Readers, We always try to publish useful circuits and topics for our readers. After publishing an article we usually measure how well it was received among our readers. We have two options for measuring success of an article published; first being the number of page views it has got and the second being
Hi All Readers of CircuitsToday, As there is serious discussions going on about our previous Automatic LED Emergency Light Circuit using LM 317, Mr.Seetharaman has come up with a modified version of the same which answers many of the doubts raised in our Comments section. Note: Mr.Seetharaman has developed a new version of Automatic LED
Overview Direct to home technology refers to the satellite television broadcasting process which is actually intended for home reception. This technology is originally referred to as direct broadcast satellite (DBS) technology. The technology was developed for competing with the local cable TV distribution services by providing higher quality satellite signals with more number of channels.
Almost all the electronic circuits mentioned in this site are designed and built on a PCB board. But you cannot build these electronic circuits if you do not know the basics of soldering. If you do not know to solder well, the solder joints will not be perfect and thus the circuit will have serious
This versatile amplifier circuit is designed and submitted by Mr Seetharaman Subramanian from Chennai . The full credit of this article goes to him and we are very proud to publish this fabulous circuit here. Seetharaman’s description about the circuit. This concept has appeared long back in Practical Electronics a UK based Magazine. Based on
Decription. The circuit given here is of a three input mic mixer cum preamplifier using the IC LM348. The LM348 is a high gain, internally compensated quad operational amplifier with a class AB output stage. The IC has very low input supply current drain (0.6mA/ opamp) and operates from a dual power supply. Out of
“] Electronic Ink [E-ink We have seen the working of electronic displays like Liquid Crystal Displays, SED TV’s, and Touch screen technology and so on. Even though we rely mostly on monitors nowadays we must not forget the fact that the basic display mechanism is paper the early 105 AD when the Chinese invented it.
On February 11th, 2010, NASA launched a new spacecraft called the Solar Dynamics Observatory [SDO], which was designed to give more knowledge and clearer images of the Sun than any other spacecraft that has been launched before for this purpose. On April 21st, 2010, the scientists of NASA have quoted their experiment with the SDO
