VLSI Multiple Choice Questions on “BiCMOS Technology”.
1. MOS technology has more load driving capability.
A. true
B. false
Answer: B
Clarification: One of the disadvantages of MOS technology is it has limited load driving capabilities.
2. What is the disadvantage of the MOS device?
A. limited current sourcing
B. limited voltage sinking
C. limited voltage sourcing
D. unlimited current sinking
Answer: A
Clarification: MOS devices have limited current sourcing and current sinking abilities.
3. What are the advantages of BiCMOS?
A. higher gain
B. high frequency characteristics
C. better noise characteristics
D. all of the mentioned
Answer: D
Clarification: BiCMOS provides higher gain, better noise and high frequency characteristics than MOS transistors.
4. What are the features of BiCMOS?
A. low input impedance
B. high packing density
C. high input impedance
D. bidirectional
Answer: A
Clarification: Some of the features of BiCMOS are low input impedance, low packing density, unidirectional, high output drive current, etc.
5. BiCMOS has low power dissipation.
A. true
B. false
Answer: B
Clarification: BiCMOS has high power dissipation and CMOS has low power dissipation.
6. CMOS is __________
A. unidirectional
B. bidirectional
C. directional
D. none of the mentioned
Answer: A
Clarification: BiCMOS is unidirectional and CMOS is bidirectional.
7. In bipolar transistor, its quality can be improved by __________
A. increasing collector resistance
B. decreasing collector resistance
C. collector resistance does not affect the quality
D. decreasing gate resistance
Answer: B
Clarification: The quality of bipolar transistor can be improved by reducing the collector resistance, which can be done by using the additional layer of n+ subcollector.
8. BiCMOS can be used in __________
A. amplifyig circuit
B. driver circuits
C. divider circuit
D. multiplier circuit
Answer: B
Clarification: BiCMOS is more advantageous and improved than CMOS and it can be used in I/O and driver circuits.
9. What are the advantages of E-beam masks?
A. small feature size
B. larger feature size
C. looser layer
D. complex design
Answer: A
Clarification: The advantages of E-beam masks are it has tighter layer to layer registration and it has smaller feature sizes.
10. Which process is used in E-beam machines?
A. raster scanning
B. vector scanning
C. raster & vector scanning
D. none of the mentioned
Answer: C
Clarification: The two approaches to the design of E-beam machines are raster scanning and vector scanning.
11. What is the feature of vector scanning?
A. faster
B. slow
C. easy handling
D. very simple design
Answer: A
Clarification: Vector scanning is faster but data handling involved is more complex. Vector scanning is done between the end points.
12. Which has high input resistance?
A. nMOS
B. CMOS
C. pMOS
D. BiCMOS
Answer: B
Clarification: CMOS technology has high input resistance and is best for constructing simple low-power logic gates.
13. BiCMOS has lower standby leakage current.
A. true
B. false
Answer: B
Clarification: BiCMOS has the potential for high standby leakage current and has high power consumption compared to CMOS.