UPSC Combined Geo-Scientist, Mains · 2021 · Mains Paper I
Q2(b). Doping gallium arsenide
Question
Would gallium arsenide be a suitable compound for a semiconductor? How could n- and p-type semiconductors be designed from it?
Answer in brief
Yes. GaAs is a III-V semiconductor; donor substitution gives n-type material and acceptor substitution gives p-type material.
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Coversgallium arsenideIII-V semiconductorn-type dopingp-type dopingband gapzinc blende
All parts of Question 2
- 2(a) ReO₃ unit cell and perovskite relation10 marks
- 2(b) Doping gallium arsenide10 marks
- 2(c)(i) Metal deficiency in wüstite5 marks
- 2(c)(ii) Solid-state and solution synthesis5 marks