ISSN:
0049-8246
Keywords:
Chemistry
;
Analytical Chemistry and Spectroscopy
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Physics
Notes:
An x-ray fluorescence technique was developed to analyze the thickness of Ag and Pd metallization layers on the back side contacts of Si solar cells. The technique employed a Sn secondary target x-ray source excited by a Cr target x-ray tube. Sn Kβ excited Ag Kα in the overlying Ag contact while Sn Kα and Kβ excited Pd Kα in the underlying Pd film. The emitted Ag and Pd Kα intensities were compared with corresponding intensities emitted from pure bulk Ag and Pd standards. Attenuation of Sn Kβ and Sn, Ag and Pd Kα in the Ag contact and in the standards was accounted for in the calculations. The results on 17 cells compared favorably with neutron activation analyses. An accuracy of ±10% was estimated for a 40 nm Pd film beneath a 7 μm Ag contact. Palladium films as thin as 1.5 nm were analyzed. The technique is nondestructive and can be applied to process control in a production environment as well as to laboratory testing of experimental cells.
Additional Material:
3 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/xrs.1300110205
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