1. 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.
2. 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.
3. 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.
4. Which region is heavily doped?
A. drain
B. gate
C. n-region
D. p-region
Answer: A
In GaAs FET, a narrow metal Schottky barrier gate separates the more heavily doped drain and source.
5. Which MOSFET contains Schottky diode?
A. GaAs
B. Ga
C. Si
D. SiO2
Answer: A
GaAs MOSFET differs from silicon MOSFET due to the presence of a Schottky diode to separate two thin n-type regions.
6. D type and E type MESFETs operates by ________ of the existing doped channel.
A. depletion
B. enhancement
C. e type MESFET
D. d type MESFET
Answer: A
D type and E type MESFETs, that is ON and OFF devices operate by the depletion of an existing doped channel.
7. Which is the ON device?
A. e type MESFET
B. d type MESFET
C. depletion
D. enhancement
Answer: B
D-MESFET is normally ‘ON’ and its threshold voltage is negative and E-MESFET is ‘OFF’ and its threshold voltage is positive.
8. The threshold voltage cannot be determined using
A. concentration density
B. channel thickness
C. implanted impurity
D. channel depth
Answer: D
The threshold voltage can be determined using concentration density, channel thickness, and implanted impurity but cannot be determined using channel depth.
9. A highly doped thick channel exhibits _______ threshold voltage.
A. smaller negative
B. smaller positive
C. larger negative
D. larger positive
Answer: C
A highly doped thick channel exhibits a large negative threshold voltage. By reducing channel thickness and concentration density, the positive threshold in E-MESFET can be fabricated.
10. The MESFET has maximum
A. gate to drain voltage
B. gate to source voltage
C. source voltage
D. drain voltage
Answer: B
The MESFET has a maximum gate to source voltage Vgs of about 0.7-0.8 volt owing to the diode action of the Schottky diode gate.
