Q. 29

Silicon doped with electron-rich impurity forms ________.
A. p-type semiconductor

B. n-type semiconductor

C. intrinsic semiconductor

D. insulator

Answer :

When Silicon is doped with an electron-rich impurity, for example, an element from Group 15 like Phosphorous and Arsenic, which has 5 valence electrons, some of the electrons will occupy some of the lattice sites in the silicon crystal. Four out of the five will form covalent bonds with the four neighbouring silicon atoms, while the remaining electron becomes delocalized and increases the conductivity of the silicon. The increase in the conductivity is caused due to increase in negative charge and thus the doped silicon is called n-type semiconductor. The correct answer is (ii).

Rate this question :

How useful is this solution?
We strive to provide quality solutions. Please rate us to serve you better.
Related Videos
Defects in solid | Solid StateDefects in solid | Solid StateDefects in solid | Solid State61 mins
Electrical & Magnetic PropertiesElectrical & Magnetic PropertiesElectrical & Magnetic Properties47 mins
Defects in solid | Solid State | Quiz TimeDefects in solid | Solid State | Quiz TimeDefects in solid | Solid State | Quiz Time49 mins
Packing efficiency and densityPacking efficiency and densityPacking efficiency and density52 mins
Packing efficiency and density | Interactive QuizPacking efficiency and density | Interactive QuizPacking efficiency and density | Interactive Quiz45 mins
Interactive Quiz on close packing in solidsInteractive Quiz on close packing in solidsInteractive Quiz on close packing in solids45 mins
Classification of solidsClassification of solidsClassification of solids65 mins
Close packing in solidsClose packing in solidsClose packing in solids46 mins
Quiz on Calculation of coordination number in solidsQuiz on Calculation of coordination number in solidsQuiz on Calculation of coordination number in solids38 mins
Interactive Quiz on classification of solids & packingInteractive Quiz on classification of solids & packingInteractive Quiz on classification of solids & packing53 mins
Try our Mini CourseMaster Important Topics in 7 DaysLearn from IITians, NITians, Doctors & Academic Experts
Dedicated counsellor for each student
24X7 Doubt Resolution
Daily Report Card
Detailed Performance Evaluation
caricature
view all courses