Advertisements
Advertisements
Question
Two crystals C1 and C2, made of pure silicon, are doped with arsenic and aluminium respectively.
Identify the extrinsic semiconductors so formed.
Advertisements
Solution
Arsenic is pentavalent. So, C1 doped with arsenic will form an n-type semiconductor.
Aluminium is trivalent. So, C2 doped with aluminium will form a p-type semiconductor.
APPEARS IN
RELATED QUESTIONS
Electronic configuration of germanium is 2, 8, 18 and 4. To make it extrinsic semiconductor small quantity of antimony is added. The correct statement is ____________.
A donor impurity results in ______.
In n-type semiconductor, the fifth electron ______.
In p-type semiconductor, the dopant is ______.
Suppose a ‘n’-type wafer is created by doping Si crystal having 5 × 1028 atoms/m3 with 1 ppm concentration of As. On the surface 200 ppm Boron is added to create ‘P’ region in this wafer. Considering n i = 1.5 × 1016 m–3, (i) Calculate the densities of the charge carriers in the n and p regions. (ii) Comment which charge carriers would contribute largely for the reverse saturation current when diode is reverse biased.
Name the extrinsic semiconductors formed when pure germanium is doped with a trivalent impurity. Draw the energy band diagram of extrinsic semiconductors so formed.
Name the extrinsic semiconductors formed when pure germanium is doped with a Pentavalent impurity. Draw the energy band diagram of extrinsic semiconductors so formed.
Pieces of copper and of silicon are initially at room temperature. Both are heated to temperature T. The conductivity of ______.
Which type of dopant is aluminium (Al)?
What are the two types of extrinsic semiconductors?
