Contact module for optimizing emitter and contact resistance
An advanced contact module for optimizing emitter and contact resistance and methods of manufacture are disclosed. The method includes forming a first contact via to a first portion of a first device. The method further includes filling the first contact via with metal material to form a first metal contact to the first portion of the first device. The method further includes forming additional contact vias to other portions of the first device and contacts of a second device. The method further includes cleaning the additional contact vias while protecting the first metal contact of the first portion of the first device. The method further includes filling the additional contact vias with metal material to form additional metal contacts to the other portions of the first device and the second device.
1. A structure, comprising:
a bipolar transistor comprising an emitter region, a base region and a collector region, a contact in direct electrical contact on a non-silicided region of the emitter region which is different than contacts of the collector region and the base region, the contacts of the collector region and the base region are in electrical contact with silicide regions of the collector region and the base region; and
a transistor having contacts in electrical contact with silicide regions, the contacts being the same as the contacts for the collector region and the base region,
wherein the bipolar transistor and the transistor are formed on a same substrate; and
the silicide region of the base region is directly on a top surface of an epitaxial layer that is directly on a top surface of the substrate.
2. The structure of claim 1 , wherein the bipolar transistor is an NPN transistor.
3. The structure of claim 2 , wherein the NPN transistor is provided on the epitaxial layer which comprises boron doped SiGe.
4. The structure of claim 1 , wherein the emitter region is polysilicon.
5. The structure of claim 4 , wherein the base region includes a base contact region and the collector region includes a collector contact region, both of nickel silicide.
6. The structure of claim 4 , wherein the base region includes a base contact region and the collector region includes a collector contact region, both of cobalt silicide.
7. The structure of claim 4 , wherein:
the epitaxial layer comprises boron doped SiGe;
the substrate is a p-type substrate;
the base region has a base contact region which is formed on the epitaxial layer; and
the collector region has a collector contact region which is formed over an n-type region on the p-type substrate that is electrically connected to the collector region of the bipolar transistor.
8. The structure of claim 1 , wherein the contact is metal material of tungsten with a Ti and TiN liner material in electrical contact with the emitter region.
9. The structure of claim 1 , wherein the substrate is a p-type substrate.
10. The structure of claim 9 , wherein the bipolar transistor is isolated from the transistor by a shallow trench isolation structure.
11. The structure of claim 10 , wherein the bipolar transistor is formed on the epitaxial layer, which comprises a boron doped SiGe layer, and the emitter region is polysilicon material.
12. The structure of claim 11 , wherein the silicide regions of the base region, the collector region and the transistor are nickel silicide or cobalt silicide.
13. The structure of claim 12 , wherein the base region has a base contact region formed on the boron doped SiGe layer and the collector region has a collector contact region formed over an n-type region on the p-type substrate that is electrically connected to the collector region.
14. The structure of claim 1 , wherein the silicide region of the collector region is on the top surface of the substrate.
15. The structure of claim 14 , wherein the silicide region of the collector region and at least one of the silicide regions of the transistor are at a same vertical height relative to the top surface of the substrate.
16. The structure of claim 15 , wherein:
the epitaxial layer comprises boron doped SiGe;
a portion of the epitaxial layer is directly on a top surface of a shallow trench isolation structure formed in the substrate; and
the top surface of the substrate is coplanar with the top surface of the shallow trench isolation structure.
17. The structure of claim 16 , wherein the contact of the collector is between the contact of the emitter and the contacts of the transistor in a horizontal direction.
18. The structure of claim 17 , wherein one of the contacts of the base is between the contact of the emitter and the contact of the collector in a horizontal direction.