Electrode-width-weighted wavelet transform processor using SAW devices
Abstract
Purpose
When designing the electrode widths of the electrode-width-weighted (EWW) input interdigital transducers (IDTs) according to the envelope amplitudes of the wavelet function, the EWW wavelet transform processor (WTP) using surface acoustic wave (SAW) devices can be fabricated. The electrode widths have influence on the frequency characteristic of the EWW WTP using SAW devices. The purpose of this research is to solve the influence of the electrode width accuracy on the frequency characteristic of the EWW WTP using SAW devices.
Design/methodology/approach
In order to solve the influence of the electrode width accuracy on the frequency characteristics of the EWW WTP using SAW devices, the function between the electrode widths and the −3 dB bandwidth is derived. That the −3 dB bandwidth varies as the electrode widths is known according to this function so that the exposure time and the etching are presented as the two key problems.
Findings
Solutions to these problems are achieved in this study. As long as there is accurate exposure time, the precision IDTs (i.e. the precision electrode widths) will be obtained. The accuracy of the exposure time for the EWW WTP using SAW devices is ±1 per cent. Because the dry etching is a type of etching technology in gas medium, it can etch nanometer lines, even more fine lines, so that the dry etching is used in EWW WTP using SAW devices.
Originality/value
Research highlights solving the influence of the electrode width accuracy on the frequency characteristic for the EWW WTP using SAW devices; deriving the function between the electrode widths and the −3 dB bandwidth (it is known from this function that the −3 dB bandwidth varies as the electrode widths); and presenting the exposure time and the etching as two key problems.
Keywords
Acknowledgements
This work was supported by the National Natural Science Foundation of China (Grant No. 61274078), the Research and Innovation Project of the Shanghai Education Commission (Grant No. 13ZZ049) and the Doctoral Science Foundation of the Ministry of Education of China (Grant No. 20120075110006).
Citation
Lu, W., Gao, L., Liu, Q., Zhang, J. and Zhang, H. (2017), "Electrode-width-weighted wavelet transform processor using SAW devices", Microelectronics International, Vol. 34 No. 2, pp. 75-83. https://doi.org/10.1108/MI-01-2016-0004
Publisher
:Emerald Publishing Limited
Copyright © 2017, Emerald Publishing Limited