Physics Electronics PMDC Conceptual Practice
PMDC Verified Question 141 of 494
Which of the following materials is classified as an elemental (pure) semiconductor?
A
Gallium Arsenide (GaAs)
B
Silicon (Si)
C
Cadmium Sulfide (CdS)
D
Indium Phosphide (InP)
Tap any option to test your recall and reveal the step-by-step Propolis autopsy.

Propolis Cognitive Error Autopsy

Official Correct Choice:
Option B: Silicon (Si)
Concept:

Elemental semiconductors consist of a single chemical element from Group IV of the periodic table, such as Silicon (Si) or Germanium (Ge). Compound semiconductors are made from two or more elements (e.g., Groups III-V or II-VI).

Formula:

$$\text{Elemental Semiconductors: } \text{Silicon (Si), Germanium (Ge)}$$

$$\text{Compound Semiconductors: } \text{GaAs, InP, CdS, GaN}$$

Solution:

  • Silicon is a single chemical element (Group IV, atomic number 14) and is the most widely used elemental semiconductor.


  • GaAs, CdS, and InP are compound semiconductors formed from combinations of different elements.


Why other options are incorrect:

  • Option A: Gallium Arsenide is a binary III-V compound semiconductor.
  • Option C: Cadmium Sulfide is a II-VI compound semiconductor.
  • Option D: Indium Phosphide is a III-V compound semiconductor.

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