Global planarization method

A method for introducing a feature into an electronic substrate during its manufacture comprising the steps of:

• a. providing a substrate having a base material layer and a first material layer applied on top of the base material layer wherein the first material layer has a thickness of at least 2 microns and wherein the first material layer has an exposed surface;
• b. depositing a first photosensitive etch resistant material layer onto the exposed surface of the first material layer;
• c. forming a first mask over the first photosensitive etch resistant material layer wherein the mask covers portions of the first photosensitive etch resistant material layer to form covered portions of the photosensitive etch resistant material layer and wherein the mask leaves portions of the first photosensitive etch resistant material layer exposed to form exposed portions of the first photosensitive etch resistant material layer;
• d. imaging the exposed portions of the photosensitive etch resistant material to give activated portions and non-activated portions of the first photosensitive etch resistant material layer;
• e. removing a portion of the first photosensitive etch resistant material layer to expose the first material layer;
• f. etching the exposed first material layer to a predetermined thickness to form a feature;
• g. removing the first photosensitive etch resistant material layer from the substrate to expose the first material layer surface;
• h. applying a stop material layer to the first material layer surface;
• i. depositing a third photosensitive etch resistant material layer onto the surface of the stop material layer;
• j. forming a mask over the third photosensitive etch resistant material layer wherein the mask covers portions of the third photosensitive etch resistant material layer and wherein the mask exposes portions of the third photosensitive etch resistant material layer;
• k. imaging the exposed portions of the third photosensitive etch resistant material layer to form activated and non-activated portions of the third photosensitive etch resistant material layer;
• l. removing the portion of the third photosensitive etch resistant material layer that lies in the feature to expose the stop material layer associated with the feature;
• and
• m. removing the exposed stop material layer from the substrate.
• n. depositing a second material layer onto the exposed substrate surface in an amount sufficient to fill the first material layer feature;
• o. depositing a second photosensitive etch resistant material layer onto the exposed surface of the first material layer;
• p. forming a second mask over the second photosensitive etch resistant material layer to form exposed portions of second photosensitive etch resistant material layer and unexposed portions of second photosensitive etch resistant material layer;
• q. imaging the exposed portions of the second photosensitive etch resistant material layer to form activated portions and non-activated portions of the second photosensitive etch resistant material layer;
• r. removing the portion of the second photosensitive etch resistant material layer that does not lie above the feature to expose portions of the second material layer;
• s. stripping at least a portion of the exposed second material layer from the substrate;
• and
• t. planarizing the surface of the substrate by chemical mechanical polishing.