Method of fabricating passivation
View Patent ↗Embodiments relate to a passivation fabricating method. In the passivation fabricating method according to embodiments, a first oxide film may be formed by repeating deposition and etching of an oxide film on a silicon substrate in which an upper metal pad may be formed and a second oxide film may be formed by performing only deposition on the first oxide film. A thickness of the first oxide film may be set to be above 5 kÅ. A first passivation layer may be formed by planarizing the first and second oxide films. In the planarizing process, a thickness of the first passivation layer may be 4 kÅ. A second passivation layer of a nitride film may be formed on the first passivation layer and the first and second passivations may be selectively etched so as to expose the upper metal pad.
1. A method comprising:
forming a first oxide layer over a silicon substrate in which a metal pad is formed;
forming a second oxide layer over the first oxide layer;
forming a first passivation layer by planarizing the first and second oxide layers;
forming a second passivation over the first passivation layer; and
selectively etching the first and second passivation layers to expose the upper metal pad.
2. The method of claim 1 , wherein first oxide layer is formed by repeating deposition and etching of oxide films.
3. The method of claim 2 , wherein the second passivation layer comprises a nitride layer.
4. The method of claim 1 , wherein the first oxide layer has a thickness of greater than approximately 5 kÅ.
5. The method of claim 4 , wherein the first oxide layer has a thickness of approximately 11 kÅ and the second oxide layer has a thickness of approximately 12 kÅ.
6. The method of claim 5 , wherein the first oxide layer is formed by an HDP process and the second oxide layer is formed by a TEOS process, and planarizing the first and second oxide layers comprises performing a Chemical Mechanical Polishing (CMP).
7. The method of claim 6 , wherein the first and second oxide layers are planarized to a thickness of approximately 4 kÅ.
8. The method of claim 1 , wherein forming the first passivation layer comprises performing the planarization so that a thickness of the first passivation layer is approximately 4 kÅ.
9. The method of claim 1 , wherein a sum of thicknesses of the first and second passivation layers is less than approximately 15 kÅ.
10. The method of claim 1 , wherein a thickness of the first passivation layer is approximately 4 kÅ and a thickness of the second passivation layer is approximately 10 kÅ.
11. The method of claim 1 , further comprising forming a metal connector in the etched portion of the first and second passivation layers, the metal connector being in electrical contact with the metal pad.
12. The method of claim 11 , wherein a top surface of the metal connector is formed to be above a top surface of the second passivation layer.