Ultrafast carrier dynamics in microcrystalline silicon probed by time-resolved terahertz spectroscopy

被引：79

作者：

Fekete, L. ^{[1
]}

Kuzel, P. ^{[1
]}

Nemec, H. ^{[1
]}

Kadlec, F. ^{[1
]}

Dejneka, A. ^{[1
]}

Stuchlik, J. ^{[1
]}

Fejfar, A. ^{[1
]}

机构：

[1] Acad Sci Czech Republic, Inst Phys, Prague 18221 8, Czech Republic

来源：

PHYSICAL REVIEW B | 2009年 / 79卷 / 11期

关键词：

electron-phonon interactions; elemental semiconductors; high-speed optical techniques; hopping conduction; hot carriers; localised states; photoconductivity; semiconductor thin films; silicon; terahertz wave spectra; time resolved spectra; CHEMICAL-VAPOR-DEPOSITION; MIXED-PHASE SILICON; RAMAN-SPECTROSCOPY; AC CONDUCTION; TRANSPORT; GROWTH; MODEL; PHOTOCONDUCTIVITY; CRYSTALLINITY; DEPENDENCE;

D O I：

10.1103/PhysRevB.79.115306

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

We present the results of optical-pump-terahertz probe experiments applied to a set of thin-film microcrystalline silicon samples, with structures varying from amorphous to fully microcrystalline. The samples were excited at wavelengths 800 and 400 nm and studied at temperatures down to 20 K. The character of nanoscopic electrical transport properties markedly change on a subpicosecond time scale. The initial transient photoconductivity of the samples is dominated by hot free carriers with a mobility of similar to 70 cm(2)/Vs. These carriers are rapidly (within 0.6 ps) trapped into weakly localized hopping states. The hopping process dominates the terahertz spectra on the picosecond and subnanosecond time scales. The saturated high-frequency value of the hopping mobility is limited by the sample disorder in the amorphous sample and by electron-phonon interaction for microcrystalline samples.

引用

页数：13

共 39 条

[1] Photoconductivity methods in materials research [J].

Brinza, M ;

Willekens, J ;

Benkhedir, ML ;

Emelianova, EV ;

Adriaenssens, GJ .

JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS, 2005, 16 (11-12) :703-713

[2] Transient terahertz conductivity in photoexcited silicon nanocrystal films [J].

Cooke, D. G. ;

MacDonald, A. N. ;

Hryciw, A. ;

Wang, J. ;

Li, Q. ;

Meldrum, A. ;

Hegmann, F. A. .

PHYSICAL REVIEW B, 2006, 73 (19)

[3] Semiconductor materials for ultrafast photoswitches [J].

Coutaz, JL .

ACTA PHYSICA POLONICA A, 2002, 102 (4-5) :495-512

[4] THE RANDOM FREE-ENERGY BARRIER MODEL FOR AC CONDUCTION IN DISORDERED SOLIDS [J].

DYRE, JC .

JOURNAL OF APPLIED PHYSICS, 1988, 64 (05) :2456-2468

[5] AC CONDUCTION IN AMORPHOUS-CHALCOGENIDE AND PNICTIDE SEMICONDUCTORS [J].

ELLIOTT, SR .

ADVANCES IN PHYSICS, 1987, 36 (02) :135-218

[6] Model of electronic transport in microcrystalline silicon and its use for prediction of device performance [J].

Fejfar, A ;

Mates, T ;

Certík, O ;

Rezek, B ;

Stuchlík, J ;

Pelant, I ;

Kocka, J .

JOURNAL OF NON-CRYSTALLINE SOLIDS, 2004, 338 :303-309

[7] Carrier dynamics in microcrystalline silicon studied by time-resolved terahertz spectroscopy [J].

Fekete, L. ;

Nemec, H. ;

Kadlec, F. ;

Kuzel, P. ;

Stuchlik, J. ;

Fejfar, A. ;

Kocka, J. .

JOURNAL OF NON-CRYSTALLINE SOLIDS, 2006, 352 (26-27) :2846-2849

[8] Real-time spectroscopic ellipsometry studies of the nucleation and grain growth processes in microcrystalline silicon thin films [J].

Fujiwara, H ;

Kondo, M ;

Matsuda, A .

PHYSICAL REVIEW B, 2001, 63 (11)

[9] ULTRAFAST DYNAMICS OF LASER-EXCITED ELECTRON DISTRIBUTIONS IN SILICON [J].

GOLDMAN, JR ;

PRYBYLA, JA .

PHYSICAL REVIEW LETTERS, 1994, 72 (09) :1364-1367

[10] Hydrogen structures and the optoelectronic properties in transition films from amorphous to microcrystalline silicon prepared by hot-wire chemical vapor deposition [J].

Han, DX ;

Wang, KD ;

Owens, JM ;

Gedvilas, L ;

Nelson, B ;

Habuchi, H ;

Tanaka, M .

JOURNAL OF APPLIED PHYSICS, 2003, 93 (07) :3776-3783

← 1 2 3 4 →