Contact plug in semiconductor device and method of forming the same
View Patent ↗Disclosed are a contact plug in a semiconductor device and method of forming the same. After a junction region where a contact plug is formed upwardly up to the bottom of a metal wire, the raised junction region and the metal wire are connected by a contact plug. Or after a first contact plug of the same area is formed on the junction region up to the bottom of the metal wires, the first contact plug is connected by a second contact plug. Thus, the width of the contact plug except for some portions is increased by maximum. It is thus possible to prevent an electric field from being concentrated and prohibit on-current from reduced, thus improving the electrical properties of devices.
1. A contact plug in a semiconductor device, wherein the contact plug is formed on a junction region of a semiconductor substrate, the contact plug having a narrow top and a wide bottom, the narrow top electrically connecting the contact plug to a single metal wire disposed above the contact plug and the wide bottom of the contact plug distributing an electric field,
wherein a width and a surface area of the wide bottom of the contact plug match a corresponding width and surface area of the junction region.
2. The contact plug as claimed in claim 1 , wherein the narrow top of the contact plug is formed to have a maximum width so that the contact plug cannot be electrically connected to neighboring metal wires in addition the one metal wire connected to the narrow top of the contact plug.
3. A contact plug in a semiconductor device, comprising:
a first wide plug formed on a junction region of a semiconductor substrate using a polysilicon layer; and
a second narrow plug formed on top of the first wide plug using a metal material and connected to one metal wire disposed above the second narrow plug,
wherein a width of the first wide plug is wider than that of the second narrow plug, and the first plug is formed only in a region where four or less second narrow plugs are formed and is formed so that the second narrow plug directly connects the junction region and the metal wire in a region where four or more second narrow plugs are formed.
4. The contact plug as claimed in claim 3 , wherein the second narrow plug comprises tungsten.
5. The contact plug as claimed in claim 3 , wherein a width and a surface area of the first wide plug match those of the junction region.
6. The contact plug as claimed in claim 3 , wherein the first wide plug is formed to have a maximum height to the extent that electrical influences are minimized without directly contacting the metal wires.
7. The contact plug as claimed in claim 3 , wherein the second narrow plug is formed to have a maximum width so that the second narrow plug cannot be electrically connected to neighboring metal wires in addition to the one metal wire connected to the second narrow plug.
8. A method of forming a contact plug in a semiconductor device, comprising:
providing a semiconductor substrate in which a junction region is formed;
forming a first plug on the junction region using a polysilicon layer;
forming an interlayer insulating film on the first plug, the junction region and the substrate;
forming a contact hole through the interlayer insulating film to the first plug; and
forming a second plug in the contact hole,
wherein a width of the first plug is wider than a width of the second plug, and the first plug is formed only in a region where four or less second narrow plugs are formed and is formed so that the second narrow plug directly connects the junction region and the metal wire in a region where four or more second narrow plugs are formed.
9. The method as claimed in claim 8 , wherein the first plug is formed by a selective epitaxial growth process.
10. The method as claimed in claim 8 , wherein the width of the first plug is the same as a width of the junction region.
11. The method as claimed in claim 8 , wherein the first plug is formed to have a maximum height to an extent that electrical influences are minimized without directly contacting metal wires formed above the interlayer insulating film.
12. The method as claimed in claim 8 , wherein the second plug comprises a metal.
13. The method as claimed in claim 12 , wherein the second plug comprises tungsten.
14. The method as claimed in claim 8 , wherein the width of the second plug is not greater than a width of a the metal wire connected to the second plug.