What are Semiconductors – Introduction, Guides & Information

Semiconductors form the heart and soul of all modern electronic devices. They have enabled the creation of microprocessors and computers which, in turn, have helped humanity to make great advances in technology. Web designer will not have the necessary tools he need without it; drivers will not have the GPS system if it has never been invented. Basically, every single thing that exists today which uses some form of computer in order for it to function properly depends on semiconductors.

In order to understand how a semiconductor works, we must first examine the material which it is made of. This material is silicon, a common element that can be found in sand and quartz. Most of the semiconductor chips and transistors manufactured today are created using silicon. The element possesses a unique property in its electron structure. Like the element of carbon, it has four electrons in its outer orbital, which allows it to form crystals. These four electrons, by forming perfect covalent bonds with four neighbouring atoms, create a lattice.

In carbon, the crystalline form is the precious diamond. But, in silicon, this crystalline form is a silvery, metallic-looking substance. Though these silicon crystals look metallic, they are not actually metals. Metals have free electrons which can move easily between atoms and, since electricity involves the flow or movement of electrons, metals are good conductors of electricity. However, since silicon crystals are involved in perfect covalent bonds, their electrons cannot move around. In fact, a pure silicon crystal is almost an insulator that allows very little electricity to flow through it. So, how can these silicon crystals be used to make semiconductors whose functions depend on electricity? Continue reading

The Different Sensors

Humans discover and learn about the world through their senses. We use these senses to guide us in what we do. If we see that the traffic light is red, we do not cross the street. If we hear a fire alarm go off, we rush towards an exit. If we taste something not to our liking, we spit it out. If we feel cold, we wear a jacket. If we smell something burning in the kitchen, we get ready to call for take-out. We rely on our senses to keep us informed about what is going on around us so that we can react appropriately to any particular situation.

We recognize the value of the senses so much that our scientists have even created technological equivalents of what nature has freely gifted us with. Thus, we have mechanical sensors that can detect motion, pressure, temperature, proximity and other kinds of stimuli. These mechanical sensors, in turn, allow us to continue discovering and learning about the environment around us.

Motion Sensors

There are a number of different methods by which motion can be sensed or detected by a device. For example, an automatic door opener, a feature usually found in malls, uses a radar-based motion detector. A device above the door emits bursts of either microwave radio energy or ultrasonic sound waves. It then waits for the energy to reflect and bounce back. If there is no one about to enter the building, the energy will bounce back in a regular pattern.

Motion Sensors

However, once someone enters the area, there will be a disturbance in the reflection pattern and the door then opens. In the case of a photo-sensor motion detector, a beam of focused light or a type of laser beam is aimed at a light sensor. If someone walks between the light source and the sensor, the path of the beam is disrupted. The sensor then registers the drop in the light level and sends a signal to its control box which emits an alarm.

Pressure Sensors

Pressure sensors typically measure the pressure of either gases or liquids. These sensors are used for either control or monitoring purposes in numerous everyday applications. There are five types of pressure measurements, namely: absolute pressure sensors, gauge pressure sensors, vacuum pressure sensors, differential pressure sensors, and sealed pressure sensors.

Pressure Sensors

Car alarm systems, for example, are some of the applications that utilize these pressure sensors. When the alarm system is turned on, the sensor measures the air pressure inside the car. If someone opens a door or a window, this pushes or pulls on the air inside the car, creating a change in the pressure, thereby triggering the alarm. Continue reading

Technology For Life

Technology has greatly impacted the lives of modern humans. These days, there seems to be no action that we can do without needing the aid of some machine or other. The advancements in technology have immensely benefited the entire human race by improving the quality of our lives in almost every area of existence. But perhaps the greatest gifts technology has given us is in the field of medicine.

There now exist machines which can detect illnesses in their very early stages so that the treatment processes can be initiated right away. There are machines that monitor every single aspect of a patient’s condition so that doctors can respond to any emergency in the same instant it occurs. Thanks to technology, humans can now live healthier, longer lives.

Blood Pressure Monitors

A blood pressure monitor, also known as a sphygmomanometer, is a device utilized to measure blood pressure. It usually consists of an inflatable cuff, a measuring unit, and an inflation bulb and valve in the case of manual instruments. Three types of monitors exist. Digital monitors have manual or automatic inflation. They are electronic and easy to use. Digital portable finger blood pressure monitors are the smallest ones in use.

Blood Pressure Monitors

They are extremely portable and also easy to operate. Manual blood pressure monitors can only be operated by a trained person. Mercury manometers are considered to be the best ones since their measurement is absolute and does not need a re-calibration.

Hearing Aids

A hearing aid is a device which can fit in or behind the wearer’s ear and is designed to amplify and modulate sounds for hearing-impaired people. A cochlear implant is a similar device but, instead of amplifying sound, it directly stimulates any functioning auditory nerves inside a person’s cochlea with an electric field. Hearing aids are relatively simple devices composed of four basic parts.

Hearing-Aids

It has a microphone which picks up sound and converts it into an electrical signal which it then sends to the amplifier. The amplifier increases the volume of the sound then transmits it to the receiver. The receiver or speaker converts the electrical signal back into sound and sends it to the ear. A hearing aid also has a battery which makes it work. Continue reading