Substrate concentration Nb which gives the doping level of the substrate is scaled by α.
42. The increase in operating frequency results in ______ in cross-talk noise.
a) increase
b) decrease
c) no change
d) doubling
Answer: a
The increase in operating frequency and reduction in rise time tr results in the increase of cross-talk noise.
43. Flicker noise is scaled by
a) 1/α2
b) α2/β2
c) 1/β2
d) β2/α2
Answer: b
Flicker noise occurs due to fluctuations of carriers trapped in the channel by surface states. It is scaled by α2/β2.
44. Scaling affects _____ generated noise.
a) internally
b) externally
c) internally and externally
d) does not generate
Answer: c
Scaling effects both internally and externally generated noise and this degrades both the production yield and the reliability of high-density chip layouts.
45. The basic figures of merit for MOS devices are
a) Minimum Feature size
b) Low Power dissipation
c) Maximum operational frequency
d) All of the mentioned
Answer: d
MOS is a method of creating transistors. MOS consists of three layers, a metal conductor, an insulating silicon layer, and a semiconductor silicon layer.
The basic merit of MOS devices are
Minimum Feature size
Low Power dissipation
Maximum operational frequency
46. For the constant field model, the scaling factors β and α are related as:
a) β = α
b) α = 2β
c) β = 1
d) β = α = 0
Answer: a
For the constant field model, the scaling factors β and α are related as β = α.
47. In Constant Voltage model, the scaling factors β and α are related as:
a) β = α
b) α = 2β
c) β = 1
d) β = α = 1
Answer: c
In the Constant Voltage model, the scaling factors β and α are related as β = 1.
In (CVD) Model We know if significant positive current flows through a. junction diode, the diode voltage will be some value near 0.7 V.
48. The scaling factor for the supply voltage VDD is:
a) 1
b) 0
c) 1/α
d) 1/β
Answer: d
The scaling factor for the supply voltage VDD is 1/β.
Vdd refers that the supply voltage pin is connected to the drain of the transistor.
49. The scaling factor of the length and width of the channel is:
a) 1, 1
b) 1/α, 1/β
c) 1/α, 1/α
d) 1/β, 1/β
Answer: c
The scaling factor of length is 1/α, and the scaling factor for width is 1/α.
The dimensions of interconnects (wires) scale down, as VLSI technology scales down by a factor called ‘scaling factor (s)’.
The scaling factor is an integer by which the dimensions of interconnects shrink down.
50. The third type of scaling model is:
a) λ-based model
b) µm based model
c) combined voltage and dimension model
d) combined voltage and electric field model
Answer: c
The third type of scaling model is known as the combined voltage and dimensions model proposed by Bergmann in 1991.
There are three types of scaling constant voltage, constant field, and lateral scaling.
In constant voltage scaling, VDD is kept constant, and the process is scaled.
For constant field scaling, the device dimensions are scaled by the parameter λ.
