• Aucun résultat trouvé

THICKNESS DEPENDENCE OF CATHODOLUMINESCENCE IN THIN FILMS

N/A
N/A
Info
Télécharger
Protected

Academic year: 2021

Partager "THICKNESS DEPENDENCE OF CATHODOLUMINESCENCE IN THIN FILMS"

Copied!
2
0
0

Chargement.... (Voir le texte intégral maintenant)

Texte intégral

(1)

HAL Id: jpa-00229662

https://hal.archives-ouvertes.fr/jpa-00229662

Submitted on 1 Jan 1989

HAL

is a multi-disciplinary open access archive for the deposit and dissemination of sci- entific research documents, whether they are pub- lished or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers.

L’archive ouverte pluridisciplinaire

HAL, est

destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d’enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.

THICKNESS DEPENDENCE OF

CATHODOLUMINESCENCE IN THIN FILMS

J. Yuan, Sébastien Berger, L. Brown

To cite this version:

J. Yuan, Sébastien Berger, L. Brown. THICKNESS DEPENDENCE OF CATHODOLUMINES- CENCE IN THIN FILMS. Journal de Physique Colloques, 1989, 50 (C6), pp.C6-177-C6-177.

�10.1051/jphyscol:1989631�. �jpa-00229662�

(2)

REVUE DE PHYSIQUE

APPLIQUEE

Colloque C6, Suppl6ment au n06, Tome 24, Juin 1989

THICKNESS DEPENDENCE OF CATHODOLUMINESCENCE IN THIN FILMS

J. YUAN, S. BERGER' ) and L.M. BROWN

Cavendish Laboratory, Madingley Road, GB-Cambridge CB3 OHE, Great-Britain

Abstract.

-

Thin film samples have been increasingly used in high resolution imaging studies of cathodoluminescence (CL) from materials, in order to achieve the smallest CL source possible[l-31. The analysis of the luminescence signals from thin film material is often hampered by the changes associated with the film thickness variation. This thickness effect has been analysed in a simple model which takes into account the diffusion of the excited states in thin films. The electron beam is assumed to provide a uniform excitation density over the entire film thickness appropriate to electron transparent films (the definition of which is also given). The intensity variation of CL signal as a function the foil thickness t is given by the formula I(t) =

To(

t

-

2L

co*

+

f

1

where L is the diffusion length of the energy carrier in a bulk sample; f is the ratio of the bulk diffusion 'velocity' L/z to that of the surface diffusion velocity s. Both physical parameters can be obtained from a plot of the CL intensity verses the film thickness. This has been applied to a number of materials such as Y203:~u3+, Y A G : C ~ ~ + , Diamond and InP. For the last two types of materials, the result of the analysis is consistent with those from other experiments[3,4]. For phosphors with a relatively large doping of luminescent ions, the saturation effect caused by an intense excitation density must be taken into account in interpreting the physical parameters deduced[5,6].

[I] Petroff P M, Lang D V Strudel J L and Logan R A, SEM, 1(1978), 325, SEM Inc. Chicago [2] Pennycook S J, Brown L M and McGovern S, Phil. Mag. 41A(1980), 589-600

[3] Myhajlenko S, Batstone J L, Hutchinson H J and Steeds J W, J. Phys. C : Solid State Phys. 17(19841, 6477-6492

[4]Sellschop J P F, 'Nuclear probe studies', in The properties of diamond (1979), ed. Field J E, Academic press.

[SIBerger S, McMullen D, Yuan J and Brown L M, Znst. Phys. Conf. Se. 78(1985), 137 [6]Berl A, Pkysica XV(1949), 361

(')present Address : AT & T Laboratories. Murry Hill, NJ 07974, U.S.A.

Article published online by EDP Sciences and available at http://dx.doi.org/10.1051/jphyscol:1989631

Références

Télécharger maintenant ( PDF - 2 Page - 207.89 KB )

Documents relatifs

Pollinator shifts, contingent evolution, and evolutionary constraint drive floral disparity in Salvia (Lamiaceae): Evidence from morphometrics and phylogenetic comparative methods

Pollinator shifts, contingent evolution, and evolutionary constraint drive floral disparity in Salvia (Lamiaceae): evidence from morphometrics and phylogenetic comparative methods.

Photometric calibration of an in situ broadband optical thickness monitoring of thin films in a large vacuum chamber

The sign of the flux change in situ (increasing for some wavelengths) during the time, the amplitude of the drift, and the strong chromaticism of the drift, made us think that

PHOTOLUMINESCENCE DECAY IN a-Si : INFLUENCE OF EXCITATION DENSITY AND n-TYPE DOPING

The original idea of the unique importance of intrinsic band tail states [1][12] should probably be changed by adding the assumption that doping creates defect states which

On the quality of climate proxies derived from newspaper reports ? a case study

Figure 4 shows the geopotential height anomalies related to snow occurrence in autumn and winter based on the NCEP- NCAR reanalysis data for the same 1958–1996 period used to

Nigeria as a linguistic terra incognita: The two languages of Lau

More specifically, Kaba Laka belongs to the Sara-Bongo-Bagirmi branch of Central Sudanic and is a variety of the Central Saraic language Kaba [ISO 639-3: ksp;

The reduction of dislocation density in GaAs by in doping: a specific interaction of in with the cores of 30° partial dislocations

The reduction of dislocation density in GaAs by in doping: a specific interaction of in with the cores of 30° partial dislocations... The reduction of dislocation density in GaAs by

Resistivity saturation effect in thin V-Al alloy films

The film exhibited the resistivity saturation effect, especially in the final series of the isothermal annealing processes. The resistivity changes during the first

On Equations of the Linear Theory of Shells with Surface Stresses Taken into Account

The equations of state (3.1) permit writing the plate equilibrium equations with the surface stresses (2.6) and (2.7) taken into account in terms of displacements w and rotations ϑ.