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Differentiate between… (Class 12 Physics 2023, Q24a)

questionbuddy.in/q/cbse-12-physics-2023-55-1-1-q24a-differentiate-between-intrinsic-extrinsic-semiconductors

PhysicsCBSE Class 12 · Board exam 2023, set 55/1/1 · 2 marks · Very short answer

CBSE Class 12 Physics 2023: question 24(a)

Set in the CBSE Class 12 board exam of 2023, paper 55/1/1, section B, question 24(a), for 2 marks. Try it first; the hints and our step-by-step solution are below.

Q24(a) · 2 marks · Very short answerSemiconductor Electronics: Materials, Devices and Simple Circuits

Differentiate between intrinsic and extrinsic semiconductors.

Source: official question paper from cbse.gov.in (PDF). See it in the full 2023 board paper, set 55/1/1.

Hints

Open one hint at a time and try again before the next.

Hint 1

Think about whether any impurity is added.

Hint 2

Compare the numbers of electrons and holes in each type.

Step-by-step solution

Each step shows the marks it earns, as an examiner would award them. Checked by an independent re-solve from the question paper.

  1. Intrinsic semiconductorExtrinsic semiconductor
    Pure semiconductor (e.g. pure Si, Ge) with no added impurity.Semiconductor doped with a suitable impurity (pentavalent or trivalent).
    1 mark
  2. IntrinsicExtrinsic
    Number of free electrons equals number of holes, ; conductivity is low at room temperature. ( in n-type, in p-type); conductivity is much higher at room temperature.
    1 mark

Answer: Intrinsic: pure, , low conductivity; Extrinsic: doped, , high conductivity.

Where the marks are

  • Pure vs doped (1 mark)
  • vs / low vs high conductivity (1 mark)

Revise the chapter

Practise this chapterBoard-style questions from Semiconductor Electronics: Materials, Devices and Simple Circuits, one at a time, marked against the answer key and marking points.Back to the full paper2023 board paper, set 55/1/1: every question, by section.

The question is transcribed from the official paper; figures are described in words. The solution, hints and chapter tag are ours. Spotted an error? Write tosupport@questionbuddy.in.