Donor and acceptor levels in the band diagramबैंड आरेख में दाता और ग्राही स्तरDonor and acceptor levels in the band diagram

NCERT Fig 14.9 · Class 12 Physics · Chapter 14 · interactive diagram

Parts and what they mean

• (a) n-type — conduction band ((a) n-प्रकार — चालन बैंड) — Most of its electrons come from the donors: at room temperature nearly all donors are ionised, but very few Si atoms are.
• Donor level ED (दाता स्तर ED) — Lies slightly below EC. A very small energy lifts an electron from ED into the conduction band, leaving a fixed + donor ion.
• Electrons from donors (दाताओं से इलेक्ट्रॉन) — Majority carriers in n-type.
• Valence band (n-type) (संयोजकता बैंड (n-प्रकार)) — Only a few thermal holes.
• Band gap (बैंड अंतराल) — Unchanged by light doping; new levels appear inside it.
• (b) p-type — conduction band ((b) p-प्रकार — चालन बैंड) — Only a few thermal electrons.
• Acceptor level EA (ग्राही स्तर EA) — Lies slightly above EV. With a very small energy an electron from the valence band jumps to EA, ionising the acceptor (−) and leaving a hole in the valence band. Equivalently, the hole sinks from EA into the valence band.
• Holes in the valence band (संयोजकता बैंड में होल) — Majority carriers in p-type; mostly due to the acceptors.
• Valence band (p-type) (संयोजकता बैंड (p-प्रकार)) — Electrons rise up and holes fall down when they gain energy.
• Band gap (बैंड अंतराल) — The acceptor level sits inside it, just above EV.

Original diagram drawn by Simple Learning Hub, based on NCERT Fig 14.9. Report a mistake