Depletion mode and enhancement mode metal-semiconductor field-effect transistors are gallium arsenide devices.
22. Second-generation gallium arsenide devices is
A. high electron mobility transistor
B. heterojunction bipolar transistor
C. high electron mobility & heterojunction bipolar transistors
D. none of the mentioned
Answer: C
High electron mobility transistor and heterojunction bipolar transistor are second-generation gallium arsenide devices.
23. Switching delays of GaAs are in the range of
A. 40-50
B. 20-30
C. 100-120
D. 70-80
Answer: D
GaAs exhibit switching delays as low as 70 to 80 per sec for low power dissipation.
24. Which device has a very high speed?
A. CMOS
B. FET
C. GaAs
D. MESFET
Answer: C
GaAs device has very high speed and low voltage swing. A bipolar device is faster than CMOS and a bit slower when compared to GaAs.
25. Which has high output drive?
A. Bipolar
B. CMOS
C. FET
D. PNP
Answer: A
A bipolar transistor has a high output drive. Whereas CMOS and GaAs have lower output drive comparatively.
26. In a bipolar device, the relationship of gm and Vin can be described as
A. directly related
B. exponentially related
C. inversely related
D. logarithmically related
Answer: B
In bipolar devices, gm is exponentially related to Vin. Mathematically it can be expressed as gm is proportional to e(Vin).
27. Which is the unidirectional device?
A. Bipolar
B. CMOS
C. FET
D. PNP
Answer: A
A bipolar device is a unidirectional device whereas CMOS and GaAs devices are bidirectional devices.
28. The gallium arsenide field-effect transistor is ________ majority carrier device.
A. bulk current insulation
B. bulk current conduction
C. bulk voltage insulation
D. bulk voltage conduction
Answer: B
The gallium arsenide field-effect transistor is a bulk current-conduction majority carrier device and is fabricated from bulk gallium arsenide.
29. Method used for fabrication of GaAs FET is
A. ion implantation
B. disposition
C. diffusion
D. conduction
Answer: A
The methods used for the fabrication of gallium arsenide field-effect transistors are high-resolution photolithography and ion implantation.
30. How many masking stages does fabrication of GaAs FET require?
A. five
B. four
C. ten
D. eight
Answer: D
The fabrication of GaAs field-effect transistor requires six to eight masking stages and processing is relatively simple.
