Patent ID: 6649504
Filing Date: 2003-11-18
Classification: H01L

Abstract:
A method for building high aspect ratio electrodes in an electrode means (E) comprising parallel electrodes (&egr;1,&egr;2) in a dense arrangement, wherein the method comprises successive process steps for:a) depositing a first global layer of electrode material (&egr;) with height h on a substrate (1); b) patterning the electrode material (&egr;) to form first parallel electrodes (&egr;1) of the electrode means (E), said first electrodes (&egr;1) having a width w and height h and being separated by a recess (2) of width d, and wherein the method is characterized by comprising successive further process steps for c) covering the first electrodes (&egr;1) with a barrier layer of thickness &dgr;, &dgr; being a fraction of width w, whereby the width d of the recess (2) becomes equal to 2w+2&dgr;; d) depositing a second global layer of electrode material (&egr;) over the first electrodes (&egr;1) with the barrier layer (3) and filling the recesses (2) therewith; e) patterning a second layer of electrode material (&egr;) to form second parallel electrodes (&egr;2) of the electrode means (E) in the recesses (2â€²) between the electrodes (&egr;1) and the barrier layer (3) covering the latter, said second electrodes (&egr;1) extending above the first electrodes (&egr;1) to a height Hâˆ’h and being insulated therefrom by means of the barrier layer (3), whereafter the sequence of process steps c)-e) are alternatingly applied as required to the first and second electrodes (&egr;1,&egr;2) respectively until the desired aspect ratio (n+1)(Hâˆ’h)/w for all electrodes is obtained in a final process step after performing n sequences of the successive process steps c)-e), a final process step comprising applying electrode material to obtain electrodes (&egr;1&egr;2) with approximately equal height (n+1)(Hâˆ’h) and then removing excess electrode material (&egr;) in a planarizing process.