Halbleiter
Prof. Yong Lei
Fachgebiet 3D Nanostrukturierung
Prof. Thomas Hannappel
Fachgebiet Photovoltaik
http://www.tu-ilmenau.de/nanostruk/
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Contents
1. Introduction and basic knowledge of semiconductors (mainly given by
Hannappel)
2. Atomic structure and band theory of semiconductors (mainly given by Lei)
3. Solid state structures of semiconductors and Intrinsic/extrinsic semiconductors
(mainly given by Lei)
4. Doping theory in semiconductors (mainly given by Hannappel)
5. Band engineering and charge transport in semiconductors (mainly given by
Hannappel)
6. P-N Junction: basic knowledges and device applications (mainly given by Lei)
7. Semiconductors for photoelectrochemical devices (Given by Hannappel)
8. Interface engineering and hetero contacts in semiconductors (given by
Hannappel)
9. Organic semiconductors and organic electronics (given by Lei)
10. Semiconductors of carbon allotropes and device applications (given by Lei)
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1. Introduction and basic knowledge of semiconductors (mainly given by Hannappel) • Defination of semiconductors
• Typical semiconductors
• Motivation of semiconsuctors: electronic and optoelectronic components
Conductivity of materials
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2. Atomic structure and band theory of semiconductors (given by Lei)
• Definition of Conductors,
Insulators and Semiconductors
based on atomic structure.
• Band structure of Conductors,
Insulators and Semiconductors.
• Semiconductors
manufacturing techniques
Silicon Copper
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3. Solid state structures of semiconductor and Intrinsic/extrinsic semiconductor (given by Lei)
Crystal structure of silicon: A silicon atom has four electrons
which it can share in covalent bonds with its neighbors.
Basic knowledge of crystal
(primitive unit cell, lattice,
fourteen lattices) and crystal
structure of typical
semiconductors.
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• Intrinsic semiconductors: energy
band diagram and charge
transport
• Extrinsic Semiconductors:
energy band diagram and
charge transport of N- and P-
semiconductors.
• Fabrication technique of N- and
P-type semiconductors
Intrinsic Semiconductors
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4. Doping theory in semiconductors (given by Hannappel)
• Doping theory in semiconductors.
• Optical properties of semiconductors.
• Knowledges about direct band-gap and indirect band-gap semiconductors.
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5. Band engineering and charge transport in semiconductors (given by Hannappel)
- Semiconductor hetero contacts
- Band structure engineering
- Charge carrier transport in semiconductors
Before contact After contact
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6. P-N Junction: knowledges and device applications (given by Lei)
• Device structure of P-N junction.
• Basic knowledges about P-N junction: depletion region, built-in potential.
• Charge transport in P-N junction: forward-biased, reverse-biased, reverse
breakdown.
• I-V characteristic of a P-N junction.
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Light-Emitting Diode (LED): a device example of P-N junction
• Photoluminescence in semiconductors.
• Device structure of LEDs.
• Working principle of LEDs.
LED:
A forward biased P-N junction
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7. Semiconductors for photoelectrochemical devices (by Hannappel)
Photoelectrochemical devices for
solar energy conversion:
- Semiconductors as absorber
- Interface charge-separating in PEC
devices - Esaki tunnel diode
Tandem solar water splitting device
Artificial photosynthesis based on
semiconductors to generate: -Electricity -Fuels
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8. Interface engineering and hetero contacts in semiconductors (given by Hannappel)
Band diagrams of hetero contacts
Interface and hetero contact formation, epitaxial growth
Defects in semiconductors and grain boundaries
Effect of grain boundaries and defects
Oxide semiconductors Charge carrier recombination &
time-resolved measurement
Semiconductor-metal interface
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9. Organic semiconductors and organic electronics (given by Lei)
• Basic knowledge of organic semiconductors.
• P-type and N-type organic semiconductors & ambipolar organic semiconductors
• Difference between inorganic and organic semiconductors
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Organic electronics based on organic semiconductors, focusing on:
• Device structure and working principle of organic light-emitting diodes (OLEDs).
• Device structure and working principle of organic field-effect transistor (OFETs).
OPV OFET OLED
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10. Semiconductors of carbon allotropes and their device applications. (Will be given by Lei)
• Allotropes of carbon:
(a) Graphite;
(b) Graphene - Nobel Prize in Physics
2010;
(c) Carbon nanotube (CNT);
(d) Fullerence (C60) – Nebel Prize in
Chemistry 1996;
(e) C70;
(f) C540;
(g) Amorphous carbon;
(h) Lonsdaleite - a hexagonal polymorph
of diamond;
(i) Diamond.
• Current research progress about
device applications of carbon
allotropes (especially C60, carbon
nanotube and graphene): focusing
on energy conversion and storage
devices, electronic devices, etc.
Nanoscale, 2015, 7, 4338-4353