東華大學圖書館 |

Language: English

Help

回圖書館首頁

手機版館藏查詢

Back

Switch To: Labeled | MARC Mode | ISBD

The Investigation of the Electronic ...

Meidanshahi, Reza Vatan.

Linked to FindBook

Google Book

Amazon

博客來

The Investigation of the Electronic Properties of Si Based Heterojucntions: A First Principle Study of a-Si:H/c-Si and GaP/Si Heterojunctions.

Record Type:	Electronic resources : Monograph/item
Title/Author:	The Investigation of the Electronic Properties of Si Based Heterojucntions: A First Principle Study of a-Si:H/c-Si and GaP/Si Heterojunctions./
Author:	Meidanshahi, Reza Vatan.
Published:	Ann Arbor : ProQuest Dissertations & Theses, : 2019,
Description:	174 p.
Notes:	Source: Dissertations Abstracts International, Volume: 80-11, Section: B.
Contained By:	Dissertations Abstracts International80-11B.
Subject:	Computational physics. -
Online resource:	http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=13859596
ISBN:	9781392136683

The Investigation of the Electronic Properties of Si Based Heterojucntions: A First Principle Study of a-Si:H/c-Si and GaP/Si Heterojunctions.
Meidanshahi, Reza Vatan.

The Investigation of the Electronic Properties of Si Based Heterojucntions: A First Principle Study of a-Si:H/c-Si and GaP/Si Heterojunctions. - Ann Arbor : ProQuest Dissertations & Theses, 2019 - 174 p.

Source: Dissertations Abstracts International, Volume: 80-11, Section: B.

Thesis (Ph.D.)--Arizona State University, 2019.

This item must not be sold to any third party vendors.

In this dissertation, I investigate the electronic properties of two important silicon(Si)-based heterojunctions 1) hydrogenated amorphous silicon/crystalline silicon (a-Si:H/c-Si) which has already been commercialized in Heterojunction with Intrinsic Thin-layer (HIT) cells and 2) gallium phosphide/silicon (GaP/Si) which has been suggested to be a good candidate for replacing a-Si:H/c-Si in HIT cells in order to boost the HIT cell's efficiency.In the first part, the defect states of amorphous silicon (a-Si) and a-Si:H material are studied using density functional theory (DFT). I first employ simulated annealing using molecular dynamics (MD) to create stable configurations of a-Si:H, and then analyze the atomic and electronic structure to investigate which structural defects interact with H, and how the electronic structure changes with H addition. I find that H atoms decrease the density of mid-gap states and increase the band gap of a-Si by binding to Si atoms with strained bonds. My results also indicate that Si atoms with strained bonds creates high-localized orbitals in the mobility gap of a-Si, and the binding of H atoms to them can dramatically decrease their degree of localization.In the second part, I explore the effect of the H binding configuration on the electronic properties of a-Si:H/c-Si heterostructure using density functional theory studies of models of the interface between a-Si:H and c-Si. The electronic properties from DFT show that depending on the energy difference between configurations, the electronic properties are sensitive to the H binding configurations.In the last part, I examine the electronic structure of GaP/Si(001) heterojunctions and the effect of hydrogen H passivation at the interface in comparison to interface mixing, through DFT calculations. My calculations show that due to the heterovalent mismatch nature of the GaP/Si interface, there is a high density of localized states at the abrupt GaP/Si interface due to the excess charge associated with heterovalent bonding, as reported elsewhere. I find that the addition of H leads to additional bonding at the interface which mitigates the charge imbalance, and greatly reduces the density of localized states, leading to a nearly ideal heterojunction.

ISBN: 9781392136683Subjects--Topical Terms:

3343998
Computational physics.

The Investigation of the Electronic Properties of Si Based Heterojucntions: A First Principle Study of a-Si:H/c-Si and GaP/Si Heterojunctions.
LDR:03434nmm a2200337 4500 001 2207125
005 20190913102453.5
008 201008s2019 ||||||||||||||||| ||eng d
020 $a 9781392136683
035 $a (MiAaPQ)AAI13859596
035 $a (MiAaPQ)asu:18710
035 $a AAI13859596
040 $a MiAaPQ $c MiAaPQ
100 1 $a Meidanshahi, Reza Vatan. $3 3434065
245 1 4 $a The Investigation of the Electronic Properties of Si Based Heterojucntions: A First Principle Study of a-Si:H/c-Si and GaP/Si Heterojunctions.
260 1 $a Ann Arbor : $b ProQuest Dissertations & Theses, $c 2019
300 $a 174 p.
500 $a Source: Dissertations Abstracts International, Volume: 80-11, Section: B.
500 $a Publisher info.: Dissertation/Thesis.
500 $a Advisor: Goodnick, Stephen Marshall.
502 $a Thesis (Ph.D.)--Arizona State University, 2019.
506 $a This item must not be sold to any third party vendors.
520 $a In this dissertation, I investigate the electronic properties of two important silicon(Si)-based heterojunctions 1) hydrogenated amorphous silicon/crystalline silicon (a-Si:H/c-Si) which has already been commercialized in Heterojunction with Intrinsic Thin-layer (HIT) cells and 2) gallium phosphide/silicon (GaP/Si) which has been suggested to be a good candidate for replacing a-Si:H/c-Si in HIT cells in order to boost the HIT cell's efficiency.In the first part, the defect states of amorphous silicon (a-Si) and a-Si:H material are studied using density functional theory (DFT). I first employ simulated annealing using molecular dynamics (MD) to create stable configurations of a-Si:H, and then analyze the atomic and electronic structure to investigate which structural defects interact with H, and how the electronic structure changes with H addition. I find that H atoms decrease the density of mid-gap states and increase the band gap of a-Si by binding to Si atoms with strained bonds. My results also indicate that Si atoms with strained bonds creates high-localized orbitals in the mobility gap of a-Si, and the binding of H atoms to them can dramatically decrease their degree of localization.In the second part, I explore the effect of the H binding configuration on the electronic properties of a-Si:H/c-Si heterostructure using density functional theory studies of models of the interface between a-Si:H and c-Si. The electronic properties from DFT show that depending on the energy difference between configurations, the electronic properties are sensitive to the H binding configurations.In the last part, I examine the electronic structure of GaP/Si(001) heterojunctions and the effect of hydrogen H passivation at the interface in comparison to interface mixing, through DFT calculations. My calculations show that due to the heterovalent mismatch nature of the GaP/Si interface, there is a high density of localized states at the abrupt GaP/Si interface due to the excess charge associated with heterovalent bonding, as reported elsewhere. I find that the addition of H leads to additional bonding at the interface which mitigates the charge imbalance, and greatly reduces the density of localized states, leading to a nearly ideal heterojunction.
590 $a School code: 0010.
650 4 $a Computational physics. $3 3343998
650 4 $a Physical chemistry. $3 1981412
650 4 $a Electrical engineering. $3 649834
690 $a 0216
690 $a 0494
690 $a 0544
710 2 $a Arizona State University. $b Electrical Engineering. $3 1671741
773 0 $t Dissertations Abstracts International $g 80-11B.
790 $a 0010
791 $a Ph.D.
792 $a 2019
793 $a English
856 4 0 $u http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=13859596