32. Which layer is used for power and signal lines?
A. metal
B. polysilicon
C. n-diffusion
D. p-diffusion
Answer: A
Metal layers are used for power and signal lines as metals has good thermal and electrical conductivity.
33. Minimum feature size for thick oxide is?
A. 2λ
B. 3λ
C. 4λ
D. λ
Answer: B
The minimum feature size for thick oxide is 3λ and the minimum separation between thin oxide regions is also 3λ.
34. Hatching is compatible with __________
A. monochrome encoding
B. bicode encoding
C. tricode encoding
D. not compatible with any encoding
Answer: A
Hatching is compatible with monochrome encoding and also may be added to color mask coding. It is designed using closely spaced lines or sticks.
35. Minimum n-well width should be ____________ micrometer.
A. 2
B. 3
C. 4
D. 6
Answer: B
The minimum width of an n-well is 3 micrometers because an n-well should be with little thickness and in it, p-type devices are formed.
36. The minimum spacing between two n-well is _____ micrometer.
A. 4
B. 5
C. 8
D. 8.5
Answer: D
The minimum spacing between two n-well is 8.5 micrometers according to the lambda-based design rules.
37. Which can bring about variations in threshold voltage?
A. oxide thickness
B. ion implantation
C. poly variations
D. all of the mentioned
Answer: D
One of the problems in manufacturing using design rules is that variation in threshold voltage occurs. And this is caused by oxide thickness, ion implantation, and poly variations.
38. What are the advantages of design rules?
A. durable
B. scalable
C. portable
D. all of the mentioned
Answer: D
Some of the advantages of generalized design rules are they are durable, scalable, portable, increase designer efficiency, and automatic translation to the final layout can be done.
39. Minimum diffusion space is __________
A. 2λ
B. 3λ
C. 4λ
D. λ
Answer: B
The minimum diffusion space is 3λ to avoid the possibility of their associated regions overlapping and conducting current.
40. Contact cuts should be ____ apart.
A. 2λ
B. 3λ
C. 4λ
D. λ
Answer: A
Two contact cuts should be 2λ apart to prevent holes from merging.
Lambda-based rules Allow first order scaling by linearizing the resolution of the complete wafer implementation.
