Hi Riccardo,

Please check the following references:
1. J. Microelectromech. Syst., vol. 6, pp. 107-118, 1997; from Senturia et
al.
2. IEEE Trans. Electr. Dev., vol. ED-25, no.10, 1241-1250, 1978; from K. E.
Petersen
I hope I could help you.

Regards,
Joao

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Joao Gaspar
INESC Microsystems and Nanotechnologies
Rua Alves Redol,9
1000-029 Lisboa
Portugal

Tel: 351-21-3100237
Fax: 351-21-3145843
email: [email protected]
http://bohr.inesc.pt
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