BAL BHARTI SCHOOL, 13, KAMLA NEHRU ROAD, CIVIL LINES, PRAYAGRAJ ART INTEGRATED PROJECT ART INTEGRATED PROJECT OF PHYSICS AND CHEMISTRY PRESENTED BY: Mohammad Zaid Khan CLASS 12-A3 Prakhar Gupta ACKNOWLEDGEMENT I WOULD LIKE TO EXPRESS MY SPECIAL THANKS TO MY CHEMISTRY TEACHER RAVI SIR AND MY PHYSICS TEACHER ANAND SIR AS WELL AS OUR PRINCIPLE RANJANA SRIWASTAVA MAM WHO GAVE ME THE GOLDEN OPPORTUNITY TO DO THIS WONDERFUL PROJECT THE ART INTEGRATED PROJECT ON SEMICONDUCTOR AND DEVICES, WHICH ALSO HELPED ME IN DOING A LOT OF RESEARCH AND I CAME TO KNOW ABOUT SO MANY NEW THINGS ABOUT SEMICONDUCTOR AND DEVICES. SECONDLY I WOULD LIE TO THANKS TO MY PARENTS AND FRIEND WHO HELPED ME A LOT OF FINALIZING THIS PROJECT WITHIN THE LIMITED TIME RANGE. CONTENT INTRODUCTION CONDUCTORS INSULATORS SEMICONDUCTOR Type of semiconductor. Difference between intrinsic and extrinsic. Difference between n-type and p-type semiconductors. COMPARISON OF CONDUCTOR, INSULATOR & SEMICONDUCTOR ON THE BASIS OF ENERGY BAND DIAGRAM APPLICATION OF SEMICONDUCTOR INTRODUCTION Semiconductor devices are electronic devices with conductivity between a good conductor and an insulator. It uses the special electrical characteristics of semiconductor materials to accomplish specific functions such as generate, control, receive, transform, and amplify signals, and convert energy. The semiconductor materials of the semiconductor device are silicon, germanium or gallium arsenide, which can be used as rectifiers, oscillators, light emitters, amplifiers, photometers, and other equipment. To distinguish them from integrated circuits, they are sometimes called discrete devices. The basic structure of most two terminal devices (i.e., crystal diodes) is a PN junction CONDUCTORS CondUctorS are materialS that permit electronS to flow freely from particle to particle. An object made of a condUcting material will permit charge to be tranSferred acroSS the entire SUrface of the object. i. Hard Drawn Copper CondUctor ii. Steel Cored Copper CondUctor (SCC) iii. CadmiUm Copper CondUctor INSULATORS InSUlator iS a material in which electric cUrrent doeS not flow freely. The atomS Of the inSUlator have tightly boUnd electronS which cannot readily move. The property that diStingUiSheS an inSUlator iS itS reSiStivity. The moSt common exampleS are non-metalS. SEMICONDUCTOR A SEMICONDUCTOR IS A MATERIAL THAT HAS INTERMEDIATE CONDUCTIVITY BETWEEN A CONDUCTOR AND INSULATOR . SILICON AND GERMANIUM ARE THE EXAMPLES OF SEMI CONDUCTORS THE MAGIC WORD SEMICONDUCTOR IS COMPOSED OF TWO WORDS SEMI & CONDUCTOR SEMI MEANS NOT COMPLETELY WHILE CONDUCTOR MEANS SOMETHING, WHICH CAN CONDUCT ELECTRICITY INTRINSIC SEMICONDUCTOR THE PURE SEMICONDUCTOR (IMPURITY LESS THAN 1 PART IN 10 ) ARE CALLED INTRINSIC SEMICONDUCTOR. EXTRINSIC SEMICONDUCTOR A SEMICONDUCTOR DOPED WITH SOME SUITABLE IMPURITY ATOMS SO AS TO INCREASE ITS NUMBER OF CHARGE IS CALLED AN EXTRINICS SEMICONDUCTOR. TYPES OF EXTRINSIC SEMICONDUCTOR DIFFERENCE BETWEEN EXTRINSIC AND INTRINSIC CONDUCTOR S.NO Intrinsic Semiconductor Extrinsic Semiconductor 1. Semiconductor in a pure form is called Intrinsic semiconductor. Semiconductor which are doped with impurity is called extrinsic semiconductor. 2. Here the change carriers are produced only due to thermal agitation. Here the change carries are produced due to thermal agitation. 3. They have low electrical conductivity. They have high electrical conductivity. 4. They have low operating temperature. They have high operating temperature. 5. At 0K, Fermi level exactly lies between conduction band and valence band. At 0K, Fermi level exactly lies closer to conduction band in “n” type semiconductor and lies near valence band in “p” type semiconductor. Example: Si, Ge, etc. Example: Si and Ge doped with AI, In, P ,As etc. DIFFERENCE BETWEEN N-TYPE AND P-TYPE SEMICONDUCTOR S.NO N-Type Semiconductor P-Type Semiconductor 1. N-type semiconductor is obtained by doping and intrinsic semiconductor with pentavalent impurity. P-type semiconductor is obtained by doping and intrinsic semiconductor with trivalent impurity. 2. Here electrons are majority carries and holes are minority carriers. Here holes are majority carries and electrons are minority carriers. 3. It has donor energy levels very close to CB. It has acceptor energy levels very close to VB. 4. When the temperature is increased these semiconductors can easily donate and electron from donor energy level to the CB. When the temperature is increased, these semiconductor can easily accept an electron from VB to donor energy level. COMPARISONOF CONDUCTORS, INSULATORS SEMICONDUCTOR ON THE BASIS OF ENERGY BAND DIAGRAM APPLICATION OF SEMICONDUCTORS Semiconductors are of great importance in electronics industry. Various combinations of n-type & p-type Semiconductors are used for making different types of electronic components , e.g., diodes, transistors, integrated circuits (IC’s),etc. Diode which is used as a rectifier is a combination of n-type and p-type Semiconductors. Transistors are prepared by sandwiching a layer of one type of semiconductor between two layers of the other type of semiconductors DIODE A diode is a semiconductor device that essentially acts as a oneway switch for current. It allows current to flow easily in one direction, but severely restricts current from flowing in the opposite direction. Diode-: “Biased p-n junction” , i.e. p-n junction with voltage applied across it. “Forward biased”: p-side more positive than n- side. “Reverse biased”: n-side more positive than p-side. p -n JUNCTION DIODE A diode is a semiconductor device that essentially acts as a oneway switch for current. It allows current to flow easily in one direction, but severely restricts current from flowing in the opposite direction. BIASING OF DIODE i. Forward biasing ii. Reverse biasing FORWARD BAISING Forward biasing means putting a voltage across a diode that allows current to flow easily. The direction of electric field is from p-side towards n-side. p-type charge carries (positive holes) in p-sides are pushed towards and across the p-n boundary. n-type carries (negative electrons) in n-side are pushed towards and across n-p boundary. Current flows across p-n boundary. REVERSE BIASING Reverse biasing means putting a voltage across a diode in the opposite direction. The voltage with reverse biasing doesn't cause any appreciable current to flow. DIFFERENCE BETWEEN FORWARD BIASING AND REVERSE BIASING Forward Biasing Reverse Biasing o Positive terminal of battery is connected to p-type and negative to n-type semiconductor. o Positive terminal of battery connected to n-type and negative terminal to p-type semiconductor. o Depletion layer is very thin. o Depletion layer is thick. o P-n junction offers very low resistance. o P-n junction offers very high resistance. o An ideal diode have zero resistance. o An ideal diode have infinite resistance. USES OF DIODE HALF WAVE RECTIFIER A half wave rectifier is defined as a type of rectifier that only allows one half-cycle of an AC voltage waveform to pass, blocking the other half-cycle. A rectifier is a device that converts alternating current (AC) to direct current (DC). It is done by using a diode or a group of diodes. FULL WAVE RECTIFIER Full-wave rectification rectifies the negative component of the input voltage to a positive voltage, then converts it into DC (pulse current) utilizing a diode bridge configuration. In contrast, half-wave rectification removes just the negative voltage component using a single diode before converting to DC. DIFFERENCE BETWEEN HALF WAVE AND FULL WAVE RECTIFIER Full-Wave Rectification Circuit Configuration Input Voltage Waveform Voltage Waveform After Rectification Voltage Waveform After Rectification Smoothing Half-wave Rectification TYPES OF DIODE PHOTO DIODE A photodiode is a semiconductor p-n junction device that converts light into an electrical current. The current is generated when photons are absorbed in the photodiode. Photodiodes may contain optical filters, built-in lenses, and may have large or small surface areas. SOLAR CELL A solar cell, or photovoltaic cell, is an electrical device that converts the energy of light directly into electricity by the photovoltaic effect, which is a physical and chemical phenomenon REFERENCE