Semiconductors (College)

by Anthony Ababat

This course is a study of semiconductor devices including the chemistry and physics of the structure of the atom and the operation of semiconductor devices based on energy level analysis. It covers all semiconductor components such as Diode (all types), Triac, Diac, SCR and UJT and PUT (Programmable Uni-junction Transistor). It also provides an in-depth discussion to Bipolar Junction Transistor (BJT), Junction Field Effect Transistor (JFET), Metal-Oxide Semiconductor FET (MOSFET) and Insulated Gate Bipolar Transistor (IGBT) Circuits. This course is intended for students who would like to pursue an Electrical and Electronics Engineering Degree. This would be a second college course in which students may enroll after successful completion of the DC Engineering Circuits course. It's an intermediate level course for all students who would like to work as technicians in the field of Electrical, Electronics, Computer, Network, Aviation, Air-Conditioning, Solar, Automation and Communications Engineering.


Program Information
Course Certification Elements
Course Standards
Course Competencies / Outcomes
  • Review technical documents to plan work.
  • Confer with other personnel to resolve design or operational problems.
  • Resolve operational performance problems.
  • Test performance of electrical, electronic, mechanical, or integrated systems or equipment.
  • Maintain electronic equipment.
  • Assemble equipment or components.
  • Maintain operational records or records systems.
  • Advise customers on the use of products or services.
  • Prepare procedural documents.
  • Assemble equipment or components.
  • Maintain electronic equipment.
  • Confer with other personnel to resolve design or operational problems.
  • Inspect finished products to locate flaws.
  • Resolve operational performance problems.
  • Test performance of electrical, electronic, mechanical, or integrated systems or equipment.
  • Fabricate devices or components.
  • Interpret design or operational test results.

Course Work Based Learning Activities
  • Industry Guest Speakers: Arrange a schedule with Electrical/Electronics Contractors to discuss the latest trend, update and required tools or equipment in Electrical and Electronics Field.
  • Field Trips: Schedule regular field trips to various events such as the event held regularly to Automation and Solar Companies in San Bernardino and Inland Empire areas.
  • Internships: Currently helping students to get real-hands on experience by connnecting them to various industries/companies.
Course Materials

Textbook: 

  • Floyd, Thomas L. Electronic Devices:Electron flow Version . 10th ed. Pearson Prentice Hall, 2018

References:

  • Meade, Russell L Foundations of Electronics: Circuits & Devices. 5th ed. Thomson Delmar Learning, 2007
  • Streetman and Banerjee Solid State Electronic Devices. 7th ed. Pearson , 2015.
  • Grob's Basic Electronics by: Mitchel Schultz 

Calculator: Any of the models or calculator brand below, accepted by EIT (Engineer In-Training) Exam.

  • Casio: All fx-115 and fx-991 models (Any Casio calculator must have “fx-115” or “fx-991” in its model name.)
  • Hewlett Packard: The HP 33s and HP 35s models, but no others.
  • Texas Instruments: All TI-30X and TI-36X models (Any Texas Instruments calculator must have “TI-30X” or “TI-36X” in its model name.)
Course Units (180 hour course)

Unit 1: Fundamentals of Semiconductor

Unit Length (Hours): 20 Hours

Unit Description:  This unit focuses on the structure of an Atom. Electronic devices such as diodes, transistors, and integrated circuits are made of a semi-conductive material. To understand how these devices work, you should have a basic knowledge of the structure of atoms and the interaction of atomic particles. An important concept introduced in this chapter is that of the pn junction that is formed when two different types of semi-conductive material are joined. The pn junction is fundamental to the operation of devices such as: the solar cell, the diode, and certain types of transistors.

Unit Competencies/Outcomes: Students will be able to classify the operation of semiconductor devices. They will be able to:

  • Describe the structure of an atom
  • Discuss insulators, conductors, and semiconductors and how they differ
  • Describe how current is produced in a semiconductor
  • Describe the properties of n-type and p-type semiconductors
  • Describe how a pn junction is formed

Unit Assessment:  Assignment and Self-Test on Section 1-1 to 1-5, Quiz on Section 1-1 to 1-5

Unit 2: Diodes and Applications

Unit Length (Hours): 20 Hours

Unit Description: In this chapter, the operation and characteristics of the diode are covered. Also, three diode models representing three levels of approximation are presented and testing is discussed. The importance of the diode in electronic circuits cannot be overemphasized. Its ability to conduct current in one direction while blocking current in the other direction is essential to the operation of many types of circuits. One circuit in particular is the ac rectifier, which is covered in this chapter. Other important applications are circuits such as diode limiters, diode clampers, and diode voltage multipliers. A datasheet is discussed for specific diodes.

Unit Competencies/ Outcomes: 

  • Interpret and use diode datasheets.
  • Troubleshoot diodes and power supply circuits
  • Test performance of electrical, electronic, mechanical, or integrated systems or equipment.
  • Build/Construct half-wave rectifiers and full-wave rectifiers. 
  • Design and analyze power supply filters and regulators 
  • Construct circuit for diode limiters and clampers.
  • Maintain electronic equipment.
  • Assemble equipment or components

Unit Assessment: Chapter 2, Self Test 2-1 to 2-10, Circuit-Action quiz 1 to 20, and Problems on Section 2-1 to 2-10

Unit 3: Special Purpose Diodes

Unit Length (Hours): 20 Hours

Unit Description: In this unit, we cover several other types of diodes that are designed for specific applications, including: the zener, varactor variablecapacitance, light-emitting, photo, laser, Schottky, tunnel, pin, step-recovery, and current  regulator diodes.

Unit Competencies/ Outcomes

  • Install Varactor diode characteristic and analyze its operation.
  • Design and Install Semiconductor components such as LEDs, quantum dots, and photodiodes.
  • Build a Voltage regulator circuits using Zener diode.
  • Identify basic characteristics of several types of diodes.
  • Troubleshoot zener diode regulators.
  • Test performance of electrical, electronic, mechanical, or integrated systems or equipment.
  • Fabricate devices or components.
  • Interpret design or operational test results.

Unit Assessment: Self test section 3-1 to 3-5, True or False Quiz 1-12, Circuit Action Quiz 1-11 and Solve Problems Section 3-1 to 3-6.

Unit 4: Bipolar Junction Transistor

Unit Length (Hours): 20 Hours

Unit Description: The invention of the transistor was the beginning of a technological revolution that is still continuing. All of the complex electronic devices and systems today are an outgrowth of early developments in semiconductor transistors. Two basic types of transistors are the bipolar junction transistor (BJT), which we will begin to study in this chapter, and the field-effect transistor (FET), which we will cover in later chapters. The BJT is used in two broad areas—as a linear amplifier to boost or amplify an electrical signal and as an electronic switch. Both of these applications are introduced in this chapter.

Unit Competencies/ Outcomes

  • Design Build voltage Amplifier circuits using Bipolar Junction Transistor (BJT).
  • Troubleshoot circuits containing BJT components.
  • Simulate circuits consisting of BJT components.
  • Install Photo Transistor components.
  • Identify various types of transistor packages.
  • Troubleshoot faults in transistor circuits. 
  • Test performance of electrical, electronic, mechanical, or integrated systems or equipment.
  • Maintain electronic equipment.

Unit Assessment: Chapter 4, true or false quiz 1 to 12, Circuit Action quiz 1-12, Self test 4-1 to 4-8, Problems 1 to 48 and Advanced Problems 50 to 54. MultiSim troubleshooting problems 55 to 62.

Unit 5: Transistor Biasing

Unit Length (Hours): 20 Hours

Unit Description: As students learned in Chapter 4, a transistor must be properly biased in order to operate as an amplifier. DC biasing is used to establish fixed dc values for the transistor currents and voltages called the dc operating point or quiescent point (Q-point). In this chapter, several types of bias circuits are discussed. This material lays the groundwork for the study of amplifiers, and other circuits that require proper biasing.

Unit Competencies/ Outcomes

  • Design and determine the dc operating point of a linear amplifier.
  • Troubleshoot voltage-divider biased circuit. 
  • Build/Construct emitter bias circuit, a base bias circuit, an emitter-feedback bias circuit, and a collector-feedback bias circuit.
  • Troubleshoot faults in transistor bias circuits.
  • Test performance of electrical, electronic, mechanical, or integrated systems or equipment.
  • Test performance of electrical, electronic, mechanical, or integrated systems or equipment.
  • Maintain electronic equipment.
  • Assemble equipment or components.

Unit AssessmentChapter 5, true or false quiz 1 to 12, Circuit Action quiz 1-10, Self test 5-1 to 5-4, Problems 1 to 60. MultiSim troubleshooting problems 55-60.

Unit 6: BJT Amplifiers

Unit Length (Hours): 20 Hours

Unit Description: What students learned about biasing a transistor in Chapter 5 are now applied in this chapter where bipolar junction transistor (BJT) circuits are used as small-signal amplifiers. The term small-signal refers to the use of signals that take up a relatively small percentage of an amplifier’s operational range. Additionally, students will learn how to reduce an amplifier to an equivalent dc and ac circuit for easier analysis, and you will learn about multistage amplifiers. The differential amplifier is also covered.

Unit Competencies/ Outcomes

  • Design and Build circuits for Common-Emitter, Common-Base and Common Collector Amplifier.
  • Construct a Multi-Stage Amplifier Circuits. 
  • Troubleshoot faults in transistor bias circuits.
  • Test performance of electrical, electronic, mechanical, or integrated systems or equipment.
  • Maintain electronic equipment.
  • Assemble equipment or components.
  • Design and build Differential Amplifier.
  • Troubleshoot amplifier circuits.

Unit AssessmentChapter 6, true or false quiz 1 to 12, Circuit Action quiz 1-10, Self test 1-19, Problems 1 to 66. 

Unit 7: Power Amplifiers

Unit Length (Hours): 20 Hours

Unit Description: Power amplifiers are large-signal amplifiers. This generally means that a much larger portion of the load line is used during signal operation than in a small-signal amplifier. This unit covers four classes of power amplifiers: class A, class B, class AB, and class C. These amplifier classifications are based on the percentage of the input cycle for which the amplifier operates in its linear region. Each class has a unique circuit configuration because of the way it must be operated. The emphasis is on power amplification. Power amplifiers are normally used as the final stage of a communications receiver or transmitter to provide signal power to speakers or to a transmitting antenna. BJTs are used to illustrate power amplifier principles.

Unit Competencies/ Outcomes

  • Design and build Class A, B and AB Power Amplifiers.
  • Troubleshoot Power Amplifiers circuit. 
  • Test performance of electrical, electronic, mechanical, or integrated systems or equipment.
  • Test performance of electrical, electronic, mechanical, or integrated systems or equipment.
  • Maintain electronic equipment.
  • Assemble equipment or components.

Unit AssessmentChapter 7, true or false quiz 1 to 12, Circuit Action quiz 1-10, Self test 1-17, Problems 1 to 43.

Unit 8: Field Effect Transistor (FET)

Unit Length (Hours): 20 Hours

Unit Description: Here we discuss the second major type of transistor, the FET (field-effect transistor). FETs are unipolar devices because, unlike BJTs that use both electron and hole current, they operate only with one type of charge carrier. The two main types of FETs are the junction field-effect transistor (JFET) and the metal oxide semiconductor field-effect transistor (MOSFET). The term field-effect relates to the depletion region formed in the channel of a FET as a result of a voltage applied on one of its terminals (gate). Recall that a BJT is a current-controlled device; that is,the base current controls the amount of collector current. A FET is different. It is a voltage-controlled device, where the voltage between two of the terminals (gate and source) controls the current through the device. A major advantage of FETs is their very high input resistance. Because of their nonlinear characteristics, they are generally not as widely used in amplifiers as BJTs except where very high input impedances are required. However, FETs are the preferred device in low-voltage switching applications because they are generally faster than BJTs when turned on and off. The IGBT is generally used in high-voltage switching applications.

Unit Competencies/ Outcomes

  • Build circuits for Junction Field Effect Transistor.
  • Construct MOSFET and IGBT (Insulated-gate Bipolar Transistor) Circuits. 
  • Troubleshoot faults in J-FET, MOSFET and IGBT circuits.
  • Test performance of electrical, electronic, mechanical, or integrated systems or equipment.
  • Maintain electronic equipment.
  • Assemble equipment or components.
  • Troubleshoot amplifier circuits.

Unit AssessmentChapter 5, true or false quiz 1 to 14, Circuit Action quiz 1-8, Self test 1-25, Problems 1 to 80 (Includes Advanced and MultiSim troubleshooting problems)

Unit 9: FET Amplifiers and Switching Circuits

Unit Length (Hours): 20 Hours

Unit Description: Because of their extremely high input resistance and low noise, FET amplifiers are a good choice for certain applications, such as amplifying low-level signals in the first stage of a communication receiver. FETs also have the advantage in certain power amplifiers and in switching circuits because biasing is simple and more efficient. The standard amplifier configurations are common-source (CS), common-drain (CD) and common-base (CB), which are analogous to CE, CC, and CB configurations of BJTs. FETs can be used in any of the amplifier types introduced earlier (class A, class B, and class C). In some cases, the FET circuit will perform better; in other cases, the BJT circuit is superior because BJTs have higher gain and better linearity. Another type of amplifier (class D) is introduced in this chapter because FETs are always superior to BJTs in class D and you will rarely see BJTs used in class D. The class D amplifier is a switching amplifier that is normally either in cutoff or saturation. It is used in analog power amplifiers with a circuit called a pulse-width modulator, introduced in Section 9–4. FETs are superior to BJTs in nearly all switching applications. Various switching circuits—analog switches, analog multiplexers, and switched capacitors—are discussed. In addition, common digital switching circuits are introduced using CMOS (complementary MOS).

Unit Competencies/ Outcomes

  • Design and Build circuits for FET using Common-Source, Common-Drain and Common Gate Amplifier.
  • Construct a Class D Amplifier Circuits. 
  • Build MOSFETs circuits for digital switching applications.
  • Troubleshoot FET amplifiers
  • Troubleshoot faults in transistor bias circuits.
  • Test performance of electrical, electronic, mechanical, or integrated systems or equipment.
  • Maintain electronic equipment.
  • Assemble equipment or components.

Unit AssessmentChapter 9, true or false quiz 1 to 15, Circuit Action quiz 1-9, Self test 1-21, Problems 1 to 62. 

Course Final Exam

FINAL EXAM - SEMICONDUCTORS


Full Name: ____________________________________                                                                    

 

 

PART 1: 80% Show your solution if calculation is required.

 

FIGURE 1

Fig._1.jpg

1. What kind of DC biasing is shown in Figure 1? 

  1. Self bias
  2. Voltage divider bias
  3. Base bias
  4. Emitter bias 

2. In Figure 1, the base current is equal to 

  1. 28. 74 µA
  2. 23.58 µA
  3. 16.5 µA
  4. None of the above


3. In Figure 1, the collector current is equal to 

  1. 4.976 mA
  2. 5.75 mA
  3. 3.3 mA
  4. None of the above

 

 4. In Figure 1, the emitter current is equal to 

  1. 5.75 mA
  2. 4.975 mA
  3. 6.5 mA
  4. None of the above

 

5. In Figure 1, the collector to emitter voltage is equal to 

  1. 12.83 V
  2. 9.25 V
  3. 8.08 V
  4. None of the above

 

6. What kind of transistor is shown in Figure 1? 

  1. NPN
  2. PNP
  3. JFET
  4. BJT
  5. Either A or D 

 

7. If one is to make Figure 1 operate as a common-base amplifier, where should the input signal be feed? 

  1. At the base
  2. At the collector
  3. At the emitter
  4. All of the above 

 

8. If one is to make Figure 1 operate as a common-base amplifier, where should the output signal be taken? 

  1. At the base
  2. At the collector
  3. At the emitter
  4. All of the above

 

9.  If one is to make Figure1 operate as a common-collector amplifier, where should the input signal be feed? 

  1. At the base
  2. At the collector
  3. At the emitter
  4. All of the above 

 

10.  If one is to make Figure 1 operate as a common-collector amplifier, where should the output signal be taken? 

  1. At the base
  2. At the collector
  3. At the emitter
  4. All of the above 

 

11. Which best describes a conducting forward-biased silicon diode?

a) Positive cathode, negative anode, voltage across = 0.7 V at 10 mA bias current

b) Positive cathode, negative anode, voltage across = 10 V at 10 mA bias current

c) Negative cathode, positive anode, voltage across = 0.7 V at 10 mA bias current

d) Negative cathode, positive anode, voltage across = 10 V at 10 mA bias current

 

12. A semiconductor diode is tested using a digital multimeter. The resistance of the diode is 10 O in both forward and reverse-biased conditions. The diode is _______. 

a) shorted

b) open 

c) not faulty

d) None of the above.

 

13. A practical diode offers _________ resistance under reverse-biased conditions if the applied reverse voltage is less than the breakdown voltage. 

a) Infinite (>100 kOhms)

b) Low (<10 Ohms)

c) Zero Ohms

d) 500 Ohms

 

14. A center-tap type rectifier uses ______. 

a) one diode

b) two diodes

c) three diodes

d) four diodes

 

15. With 10mA forward bias current, the voltages at the anode and cathode of a diode in a circuit are found to be the same. The diode is most likely to be ______. 

a) open

b) shorted

c) installed backwards

d) not faulty

 

16. A sample of intrinsic semiconductor at room temperature ______. 

a) acts as a perfect insulator

b) acts as a perfect conductor

c) has no free electrons, all electrons are tied to the atoms

d) has free electrons that are unattached to any atom

 

17.  A diode limiting circuit ______.

a) removes part of the input voltage

b) inserts a dc level voltage

c) produces an output equal to the average value of the input voltage

d) increases the peak value of the input voltage

 

18. During the positive half cycle of the input voltage in a 4 diode bridge rectifier, ____________.

a) one diode is forward biased

b) all diodes are forward biased

c) all diodes are reverse biased

d) two diodes are forward biased

e. None of the above

 

19.  The process of adding impurity atoms to a pure semiconductor material is called_______.

a) recombination

b) crystallization

c) bonding

d) doping


20. If a single diode in a center tapped full wave rectifier opens, the output is _______. 

a) 0 V

b) half wave rectified

c) increased in amplitude

d) not affected

 

21. A zener diode is always used in the forward-biased condition.

a) True

b) False

 

22. For normal linear operation of an npn transistor, the base voltage must be_______.

a) disconnected

b) negative with respect to the emitter

c) positive with respect to the emitter

d) positive with respect to the collector 

 

23. The n-type regions in an npn transistor are _______. 

a) collector and base

b) collector and emitter

c) base and emitter

d) emitter, base and collector

 

24. Two currents that are approximately the same in a normally operating npn transistor are _______. 

a) collector and base

b) base and emitter

c) collector and emitter

d) None of the above.

 

25. When an AC signal is supplied to a CE amplifier, the input signal moves the operating point _____. 

a) along the DC load line

b) along the AC load line

c) between the AC and DC load lines

d) nowhere 

 

26. In order for a transistor to operate correctly as an amplifier, ________.

a. the base-emitter junction is forward-biased

b. the base-emitter junction is reverse biased

c. the base-collector junction should be equal to 0 V

d. the base-emitter and base-collector bias must be the same

e. None of the above

 

 

27. For a transistor operation in general, ________.

a. a large base current controls a small collector current

b. emitter current controls collector current

c. collector current controls base current

d. a small base current controls a large collector current

 

28. A cutoff transistor has ________.

a. Vce = 0

b. Vce = Vcc

c. Vce cannot be determined at cut-off.

d. None of the above.

 

29. A saturated bipolar transistor can be recognized by________.

a. a very small voltage between the collector and emitter

b. Vcc voltage between the collector and the emitter

c. base current = 0

d. base reversed-biased

e. None of the above

 

 

30. In a Common Emitter amplifier, the capacitor from emitter to ground is called a________.

a. coupling capacitor

b. decoupling capacitor

c. bypass capacitor

d. tuning capacitor

 

31. If the capacitor from emitter to ground in a Common Emitter amplifier is removed, the voltage gain ________.

a. increases

b. decreases

c. is not affected

d. becomes erratic 

 

32. In a normally operating Common Emitter amplifier, if the collector resistor is increased in value, the voltage gain________.

a. increases

b. decreases

c. is not affected

d. becomes erratic

 

33. The JFET is a ______.

a. unipolar junction device

b. bipolar junction device

c. tripolar junction device

d. junction-free device

 

34. The voltage gain of an emitter follower is ______.

a. infinite

b. approximately 1

c. zero

d. greater than 1000

 

35. A MOSFET may be damaged by electrostatic discharge if it is not handled properly.

a. True

b. False

 

36. When a BJT is used as a Switch, its stable operating points are ______.

a. active and saturation

b. active and cut-off

c. cut-off and saturation

d. active, saturation, and cut-off

37.  In normal operation, the gate to source resistance of a JFET is much higher than the base to emitter resistance of a BJT.

a. True

b. False

38. Which of the following is not a JFET amplifier configuration?

a. CS

b. CE

c. CD

d. CG

 

39. An amplifier that inverts the signal between input and output is a common- ________. a. gate

b. source

c. drain

d. None of the above.

 

40. In normal operation, the gate-source pn junction for a JFET is ________. 

a. reverse-biased

b. forward-biased

c. neutral biased

d. all of the above


PART II. 20% (Refer to figures below for questions 41-50)

Part_II_Figures.jpgPart_II_Figures_9_12.jpg

41. Refer to Fig. 11. VDD = 15 V, VG-S = - 4 V, ID = 5 mA. What is RS?

a. 100 O

b. 200 O

c. 400 O

d. 800 O

e. None of the above

 

42. Refer to Fig. 11. If Q1 is replaced with an E-MOSFET, what will happen to VGS?

a. It will become less negative.

b. It will become zero.

c. It will remain the same.

d. It will cause the transistor to saturate.

e. None of the above 

 

43. Refer to Fig. 8. This is what type of transistor?

a. P-Channel E-MOSFET

b. N-Channel E-MOSFET

c. P-Channel D-MOSFET

d. N-Channel D-MOSFET

e. None of the above

 

 

44. Refer to Fig. 12. If Vgs= 0.4 V and Is= 0.8 mA, where Vgs and Is are ac values, what is gm?

a. 2 mS

b. 500 S

c. 32 mS

d. Cannot be determined.

 

REFER TO FIG. 13 FOR QUESTIONS #5-#9

45. What is the AV for the first stage if the capacitor C3 is open?

a. -198

b. -66

c. -42

d. -10

e. None of the above 

 

46. What is the AV of the second stage with the given output load resistor?

a. -199

b. -67

c. -35

d. -11

e. None of the above 

 

47. ßDC=ßac=150 for transistors. What is the output peak voltage of the two stage amplifier if the input peak voltage is 0.1 mV ? (All voltages are peak values)

a. 0.1 V

b. 0.5 V

c. 1.2 V

d. 0.2 V

e. None of the above 

 

48. If the emitter capacitor on the second stage opened, ________.

a. there would be no AC output

b. the AC output would remain the same

c. AV would increase

d. AV would decrease

e. None of the above

 

49. The purpose of the capacitor between the two stages is to ________.

a. couple the AC signal and block the DC voltage

b. develop the DC collector voltage on the first stage

c. decrease the gain of the first stage

d. provide negative feed-back for the second stage

e. None of the above

 

50. What would happen to the overall voltage gain if R9 were increased from 1 kO to 5 kO?

a. It would increase.

b. It would decrease.

c. It would remain the same.

d. Cannot be determined.

 



Course Summative Assessment

See final exam, above.