The impact of thermal annealing and adhesion film thickness on the resistivity and the agglomeration behavior of titanium/platinum thin films

Schmid, Ulrich

doi:doi:10.1063/1.2838229

Volume/Page
Keyword
DOI
Citation
Advanced

Volume: Page/Article:

Search Content Type

article doi:

Citation:

Thermal emittance and response time measurements of negative electron affinity photocathodes

The thermal emittance and temporal response of a photocathode set an upper limit on the maximum achievable electron beam brightness from a photoemission electron source, or photoinjector. We present measurements of these parameters over a broad range of laser wavelength for two different negative electron affinity (NEA) photocathodes. The thermal emittance of NEA GaAs and GaAsP has been measured by two techniques—a measurement of the beam size downstream from a solenoid, whose strength was vari...

Unified upper bound for photothermal and photovoltaic conversion efficiency

The available work (exergy) of thermal radiation is derived ab initio by using a simple statistical thermodynamic approach. A general upper bound for the efficiency of thermal radiation conversion into work is derived. This efficiency is different from the Carnot efficiency and generalizes the Petela efficiencylike factor appearing in the available work of blackbody radiation. The maximum efficiencies of photothermal and photovoltaic conversions, are particular cases of this general result. One...

In this study, the influence of postdeposition annealings (PDA) up to temperatures of T_PDA = 900 °C on the room-temperature resistivity of e-beam evaporated titanium/platinum (Ti/Pt) bilayers on Si/SiO₂ substrates is investigated. The thickness of the adhesion promoter is fixed to d_f,Ti = 15 nm. In contrast, the Pt layer is varied between d_f,Pt = 23 and 90 nm. In the “as deposited” state, an effective mean-free path for the electrons of 18 nm is extracted from the thickness-dependent electrical measurements, in reasonable agreement with theoretical predictions. Up to T_PDA = 450 °C, the dependence between the reciprocal platinum film thickness and the corresponding resistivity is linear, as expected from the size effect. At T_PDA = 450 °C, the resistivity is substantially increased independent of Pt film thickness. Due to an enhanced diffusion of titanium into the top layer the conductivity decreases preferentially at samples with d_f,Ti = 15 nm compared to those with a lower adhesion promoter thickness of 5 or 10 nm. Above this annealing range, this effect is more pronounced, especially at a low platinum film thickness. In addition, thermal grooving effects occur which are more facilitated at higher T_PDA levels and larger values for d_f,Ti. Upon annealing at T_PDA ≥ 1000 °C, the onset of a capillary-driven agglomeration process is detected. When applying a thicker adhesion promoter, a higher annealing level and/or a larger duration at T_PDA is requested to complete the agglomeration process.

Article Outline

INTRODUCTION
DEVICE PREPARATION AND EXPERIMENTAL PROCEDURE
RESULTS
1. Electrical and morphological investigations of Ti/Pt samples annealed up to 900 °C
2. Surface morphology of Ti/Pt samples annealed at T_PDA = 1000 and 1050 °C
DISCUSSION
SUMMARY AND CONCLUSIONS

RELATED DATABASES

To view database links for this article, you need to log in.

KEYWORDS and PACS

Keywords

adhesion, annealing, electrical resistivity, electron mean free path, metallic thin films, platinum, size effect, titanium, vacuum deposited coatings

PACS

73.61.At

Metal and metallic alloys
68.60.Wm

Other nonelectronic physical properties
81.40.Rs

Electrical and magnetic properties related to treatment conditions

ARTICLE DATA

Digital Object Identifier

http://dx.doi.org/10.1063/1.2838229

PUBLICATION DATA

ISSN

0021-8979 (print)

1089-7550 (online)

Publisher

$abstract.society.value is a Member of CrossRef

American Institute of Physics

For access to citing articles, you need to log in.

Figures (13) Tables (1)

Access to article objects (figures, tables, multimedia) requires a subscription; log in to view available files.
(Access to supplementary files, where available, is free for this journal.)