The addition of a very small quantity of aluminium to a silicon or ger...
Doping is the process of adding impurities to intrinsic semiconductors to alter their properties. Normally Trivalent and Pentavalent elements are used to dope Silicon and Germanium. When an intrinsic semiconductor is doped with Trivalent impurity it becomes a P-Type semiconductor.
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The addition of a very small quantity of aluminium to a silicon or ger...
Explanation:
P-type semiconductor:
When a small quantity of impurity atoms such as aluminum, boron or gallium are added to pure semiconductor materials such as silicon or germanium, it creates a material called P-type semiconductor. P-type semiconductor is created by doping a small quantity of trivalent impurity atoms in the pure semiconductor material. In P-type semiconductor, the majority carriers are holes and the minority carriers are electrons.
Working principle:
When a small quantity of aluminum is added to a silicon or germanium crystal, a P-type semiconductor is created. The aluminum atoms have only three valence electrons compared to the four valence electrons of the silicon or germanium atoms. This creates a hole in the crystal lattice structure of the silicon or germanium material.
As a result, the P-type semiconductor material has an excess of holes or positive charge carriers. When a voltage is applied across the P-type semiconductor material, these holes act as charge carriers and move towards the negative terminal of the voltage source.
Applications:
P-type semiconductor materials are widely used in the fabrication of electronic devices such as transistors, diodes, and integrated circuits. P-type semiconductors are used in the base layer of bipolar junction transistors (BJTs) and metal-oxide-semiconductor field-effect transistors (MOSFETs).
Conclusion:
Hence, the addition of a very small quantity of aluminum to a silicon or germanium crystal makes it a P-type semiconductor material. P-type semiconductors have an excess of holes or positive charge carriers, and they are widely used in electronic devices.
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