What semiconductor materials are used in manufacturing transistors___________________?
Show answer Hide answer
Answer: D. germanium
Explanation
Germanium and silicon are the primary semiconductor materials traditionally used in manufacturing electronic transistors. These elements possess crystal lattice structures with electrical conductivity levels between conductors and insulators. Germanium played a vital role in early semiconductor history before silicon became dominant due to temperature stability. Semiconductors have four valence electrons, allowing them to form strong covalent bonds with neighboring atoms. Doping pure germanium with impurities like arsenic or indium creates n-type and p-type semiconductor regions. The band gap energy of germanium is smaller than that of silicon, making it sensitive to thermal variations.
Early computers and audio amplifiers relied heavily on germanium transistors before silicon technology advanced further. Modern semiconductor fabrication plants primarily process high purity silicon wafers for microprocessors and memory chips. Specialized infrared optics and high speed diodes still utilize germanium for its unique optical and electronic properties. Silver is an extremely efficient metallic electrical conductor rather than a semiconductor material. Gold is a noble metal used for corrosion resistant wire bonding rather than for transistor substrates. Copper serves as standard wiring material for electrical distribution due to its high metallic conductivity.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
Related questions
Q1. What is the typical specific gravity of standard diesel fuel_________________?
Show answer Hide answer
Answer: C. 0.85
Standard diesel fuel has a specific gravity typically around 0.85 at standard reference temperatures. Specific gravity is a dimensionless ratio comparing the density of diesel to the density of pure water. This value con...
Q2. How does the oscillation period of a floating body change when its metacentric height is increased_________________?
Show answer Hide answer
Answer: C. lower
The oscillation period of a floating body is inversely proportional to the square root of its metacentric height. A higher metacentric height increases restoring righting moments, causing the body to snap back faster fro...
Q3. Under what conditions is the tensile strength of wrought iron at its maximum _________________?
Show answer Hide answer
Answer: A. along the lines of slag distribution
Wrought iron manufacturing processes leave elongated fibrous slag inclusions embedded in the metal matrix. Tensile loads applied along the fiber direction engage the maximum strength of the iron. Cross-grain loading expl...
Q4. What are the standard measurement units for dynamic or absolute viscosity__________________?
Show answer Hide answer
Answer: C. newton-sec per meter
Dynamic viscosity has dimensional units of force-time per unit area of fluid layer. These dimensions correspond directly to newton-seconds per meter squared in standard SI units. Educational texts frequently simplify thi...
Q5. What inventory control methodology involves the two-bin system_________________?
Show answer Hide answer
Answer: A. ordering procedure
The two-bin system is a classic inventory control and ordering procedure used to manage stock levels efficiently. When the first bin empties completely, a replenishment order is triggered while inventory is drawn from th...
Q6. When is the total pressure force on a submerged flat surface calculated simply as area multiplied by centroidal pressure intensity___________________?
Show answer Hide answer
Answer: D. all of the above
Hydrostatic pressure calculation relies only on the vertical depth of the geometric centroid. Integrating pressure over horizontal, vertical, or inclined flat surfaces yields the exact same formula. Total force equals th...