| |
Records |
Links |
|
Author |
de de Meux, A.J.; Bhoolokam, A.; Pourtois, G.; Genoe, J.; Heremans, P. |
|
| |
Title |
Oxygen vacancies effects in a-IGZO : formation mechanisms, hysteresis, and negative bias stress effects |
Type |
A1 Journal article |
| |
Year  |
2017 |
Publication |
Physica status solidi : A : applications and materials science |
Abbreviated Journal |
Phys Status Solidi A |
|
| |
Volume |
214 |
Issue |
6 |
Pages |
1600889 |
|
| |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
|
| |
Abstract |
The amorphous oxide semiconductor Indium-Gallium-Zinc-Oxide (a-IGZO) has gained a large technological relevance as a semiconductor for thin-film transistors in active-matrix displays. Yet, major questions remain unanswered regarding the atomic origin of threshold voltage control, doping level, hysteresis, negative bias stress (NBS), and negative bias illumination stress (NBIS). We undertake a systematic study of the effects of oxygen vacancies on the properties of a-IGZO by relating experimental observations to microscopic insights gained from first-principle simulations. It is found that the amorphous nature of the semiconductor allows unusually large atomic relaxations. In some cases, oxygen vacancies are found to behave as perfect shallow donors without the formation of structural defects. Once structural defects are formed, their transition states can vary upon charge and discharge cycles. We associate this phenomenon to a possible presence of hysteresis in the transfer curve of the devices. Under NBS, the creation of oxygen vacancies becomes energetically very stable, hence thermodynamically very likely. This generation process is correlated with the occurrence of the negative bias stress instabilities observed in a-IGZO transistors. While oxygen vacancies can therefore be related to NBS and hysteresis, it appears unlikely from our results that they are direct causes of NBIS, contrary to common belief. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000403339900012 |
Publication Date |
2017-03-02 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1862-6300 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
1.775 |
Times cited |
8 |
Open Access |
Not_Open_Access |
|
| |
Notes |
|
Approved |
Most recent IF: 1.775 |
|
| |
Call Number |
UA @ lucian @ c:irua:144219 |
Serial |
4678 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Branchaud, S.; Kam, A.; Zawadzki, P.; Peeters, F.M.; Sachrajda, A.S. |
|
| |
Title |
Transport detection of quantum Hall fluctuations in graphene |
Type |
A1 Journal article |
| |
Year |
2010 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
|
| |
Volume |
81 |
Issue |
12 |
Pages |
121406,1-121406,4 |
|
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
|
| |
Abstract |
Low-temperature magnetoconductance measurements were made in the vicinity of the charge neutrality point (CNP). Two origins for the fluctuations were identified close to the CNP. At very low magnetic fields there exist only mesoscopic magnetoconductance quantum interference features which develop rapidly as a function of density. At slightly higher fields (>0.5 T), close to the CNP, additional fluctuations track the quantum Hall (QH) sequence expected for monolayer graphene. These additional features are attributed to effects of locally charging individual QH localized states. These effects reveal a precursor to the quantum Hall effect since, unlike previous transport observations of QH dot charging effects, they occur in the absence of quantum Hall plateaus or Shubnikov-de Haas oscillations. From our transport data we are able to extract parameters that characterize the inhomogeneities in our device. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000276248900026 |
Publication Date |
2010-03-09 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
3.836 |
Times cited |
25 |
Open Access |
|
|
| |
Notes |
; We would like to acknowledge important motivating discussions with Louis Gaudreau, Ghislain Granger, Pawel Hawrylak, Devrim Guclu, Josh Folk, and Mark Lundeberg. A. S. S. and F. M. P. acknowledge funding from CIFAR. A. S. S. and S. B. acknowledge assistance from NSERC. ; |
Approved |
Most recent IF: 3.836; 2010 IF: 3.774 |
|
| |
Call Number |
UA @ lucian @ c:irua:82275 |
Serial |
3723 |
|
| Permanent link to this record |
