288. A junction transistor
A. is made from three separate single crystals
B. is a continuous single-crystal structure
C. is polycrystalline
D. contains two single crystals separated by a polycrystalline region

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289. In the grown-junction transistor
A. emitter is grown first
B. only doner impurities are used
C. collector region is grown first
D. contacts are made during the crystal growth

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290. In the alloy transistor, the relative magnitudes of the resistivities of the regions are
A. collector high, base medium, emitter low
B. collector low, base high, emitter high
C. collector high, base low, emitter high
D. collector low, base high, emitter low

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291. The alloy transistor has a
A. high saturation resistance
B. low saturation resistance
C. high emitter resistance
D. high base resistance

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292. The alloy transistor
A. has a frequency response limited to about 20 Mc
B. can only be a low-power device
C. has a high punch-through voltage
D. has a very thin base width

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293. Etching a semiconductor is usually accomplished by
A. polishing with an abrasive
B. sand blasting
C. heating and cooling
D. immersing in an acid solution

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294. A diffused-junction transistor
A. can be fabricated with a very thin base region
B. operates only at low frequency
C. operates only at a very low voltage
D. does not need a base cantact

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