VLSI Design Questions and Answers - Stick Diagram

1. Which color is used for implant?
a) red
b) blue
c) green
d) yellow

Answer: d
Explanation: Yellow color is used to represent implant layer

2. Which color is used for contact areas?
a) red
b) brown
c) black
d) blue

Answer: c
Explanation: Black color is used to represent contact areas. This is the part where two different touch or cross each other

3. Which color is used for polysilicon?
a) brown
b) red
c) white
d) orange

Answer: b
Explanation:Red is used to represent polysilicon layers. It is a semi-conductor like material and is a hyper pure form of silicon.

4. Which color is used for polysilicon 2?
a) blue
b) brown
c) orange
d) white

Answer: c
Explanation: Orange color is used to represent polysilicon-2 layer.

5. Which color is used for buried contact?
a) black
b) white
c) green
d) brown

Answer: d
Explanation: Brown color is used to represent buried contact. Buried contact is most widely used, subject to fewer design rule restrictions are smaller in area

6. n and p transistors are separated by using __________
a) differentiation line
b) separation line
c) demarcation line
d) black line

Answer: c
Explanation: Demarcation line separates n and p transistors. Demarcation line is similar to dotted line in brown.

7. _______ layer should be over ______ layer.
a) ntype, polysilicon
b) polysilicon, ntype
c) ptype, ntype
d) ntype, ptype

Answer: b
Explanation: Polysilicon layer should be over n-type layer. This is the standard pattern used in stick diagram representation.

8. Implant is represented using ___________
a) black, dark line
b) black, dotted line
c) yellow, dark line
d) yellow, dotted line

Answer: d
Explanation: Implant is represented using yellow color dotted lines. It is drawn in the middle of the nMOS or pMOS wherever the implant is used

9. When two or more cuts of same type cross or touch each other, that represents ____________
a) contact cut
b) electrical contact
c) like contact
d) cross contact

Answer: b
Explanation: When two or more sticks of same type cross or touch each other, then that forms a contact called electrical contact

10. Circuit design concepts can also be represented using a symbolic diagram.
a) true
b) false

Answer: a
Explanation: Circuit design concepts can be represented using stick diagrams and symbolic diagrams. Stick diagrams represents different layers with color codes. Symbolic diagram represents the structure with symbols with color codes