Methods for adjusting adhesion strength during sensor processing
The present disclosure is directed to systems and methods for adjusting adhesion strength between materials during semiconductor sensor processing. One or more embodiments are directed to using various surface treatments to a substrate to adjust adhesion strength between the substrate and a polymer. In one embodiment, the surface of the substrate is roughened to decrease the adhesive strength between the substrate and the polymer. In another embodiment, the surface of the substrate is smoothed to increase the adhesive strength between the substrate and the polymer.
1. A method comprising:
treating a surface of a substrate to increase an average roughness value of the surface of the substrate;
applying a polymer to the surface of the substrate;
curing the polymer in a manner that causes the polymer to shrink, wherein shrinking the polymer and roughening the surface of the substrate reduces an adhesive bond between the polymer and the surface of the substrate; and
forming a sensor on the polymer.
2. The method of claim 1 , wherein the polymer is polyimide.
3. The method of claim 2 , wherein applying a polymer to the surface of the substrate comprises applying the polyimide at a center portion of the surface of the substrate and rotating the substrate.
4. The method of claim 1 , wherein the substrate comprises glass.
5. The method of claim 4 , wherein the glass is boro-aluminosilicate glass.
6. The method of claim 1 , wherein roughening a surface of a substrate comprises etching the surface of the substrate.
7. The method of claim 6 , wherein etching the surface of the substrate comprises etching the surface of the substrate with fluid.
8. The method of claim 7 , wherein the fluid comprises at least one of sulfuric acid, deionized water, and hydrogen peroxide.
9. The method of claim 1 , wherein forming the sensor comprises forming a flexible glucose sensor.
10. A method comprising:
etching a surface of a glass substrate to roughen the surface;
depositing polyimide to the roughened surface of the glass substrate, the polyimide having first dimensions;
curing the polyimide;
shrinking the polyimide to second dimensions when cured, wherein etching and shrinking the polyimide reduces an adhesive bond between the polymer and the surface of the substrate; and
forming a sensor on the polyimide.
11. The method of claim 10 , wherein etching the surface of the substrate comprises a etching the surface of the substrate in a fluid.
12. The method of claim 11 , wherein the fluid is sulfuric acid.
13. The method of claim 10 , wherein curing the polyimide comprises baking the polyimide at a temperature above 300° C.
14. The method of claim 10 , wherein depositing polyimide to the roughened surface of the substrate comprises applying the polyimide at a center portion of the roughened surface and rotating the substrate.
15. The method of claim 10 , wherein the glass substrate comprises boro-aluminosilicate.
16. The method of claim 10 , wherein forming the sensor comprises forming a flexible sensor on the polyimide.
17. The method of claim 10 , wherein the surface of the substrate has a first average roughness value, and wherein etching the surface of the glass substrate comprises etching the surface of the glass substrate so that the surface of the substrate has a second average roughness value that is greater than the first average roughness value.
18. A method comprising:
treating a surface of a substrate that increases an average roughness value of the surface of the substrate;
applying polyimide to the surface of the substrate;
curing the polyimide thereby causing the polyimide to shrink, wherein shrinking the polymer and increasing the roughness of the surface of the substrate reduces an adhesion strength between the polymer and the surface of the substrate; and
forming a sensor on an exposed surface of the polyimide.
19. The method of claim 18 , wherein treating the surface of the substrate comprises roughening the surface of the substrate by etching the surface of the substrate.
20. The method of claim 18 , wherein the substrate is boro-aluminosilicate glass.