Electrode structure for a semiconductor device

• US 5,973,408 A
• Filed: 06/25/1997
• Issued: 10/26/1999
• Est. Priority Date: 12/27/1996
• Status: Expired due to Term

• Current Assignee: Nagano Keiki Seisakusho, Ltd.
• Original Assignee: Nagano Keiki Seisakusho, Ltd.
• Inventors: Sugisaki, Kouichiro, Nagasaka, Hiroshi, Uehara, Daiji
• Primary Examiner(s): Hardy, David B.
• Application Number:
  US08/882,191
• Time in Patent Office: 853 Days
• Field of Search: 257/915, 257/751
• US Class Current: 257/751
• CPC Class Codes: H01L 23/485 consisting of layered constructions comprising conductive layers and insulating layers, e.g. planar contacts H01L23/4821, H01L23/4822, H01L23/4824, H01L23/4825 take precedence; materials H01L23/532, bond pads H01L24/02, bump connectors H01L24/10
• CPC Class Codes: H01L 29/456 on silicon
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00

Abstract

An electrode structure for a semiconductor device is formed on the semiconductor device, consisting of silicon formed on a substrate to detect a physical quantity of the substrate and converting it into an electric signal, and transfers the converted electric signal to the outside. The electrode structure for the semiconductor device has a barrier layer consisting of a high-melting metal nitride and formed on a contact area of the semiconductor device and an electrode wiring formed on the barrier layer. The barrier layer has different composition ratios of the high-melting metal nitride in correspondence to each stage in the thickness of the barrier layer, in which the composition ratios are a composition ratio making a powerful bond performance at a bonding border area with the electrode wiring, and a composition ratio in which a metal element of the electrode wiring does not diffuse into the semiconductor in the barrier layer.

Claims

1. An electrode structure for a semiconductor device, which is formed on the semiconductor device, consisting of silicon formed on a substrate, and for detecting a physical quantity of the substrate and converting it into an electric signal, and transferring the electric signal to the outside, comprising:

a barrier layer consisting of a high-melting metal nitride and formed on a contact area of the semiconductor;

an electrode wiring formed on the barrier layer, the barrier layer having a multilayered structure laminated with films of said high-melting metal nitride, consisting of nitrides of the same metal each having a different composition ratio from one another, said barrier layer having therein a barrier performance which prevents the metal composing said electrode wiring from diffusing into the semiconductor device, and the composition ratio of said high-melting metal nitride forming said barrier layer, being defined to have a strong bonding force with a matter bonded with said barrier layer, in at least any one of a bonding border area between said barrier layer and said electrode wiring, and a bonding border area between said barrier layer and the contact area;

wherein said high-melting metal nitride is a titanium nitride;

wherein said barrier layer has a first titanium nitride film located to contact with said electrode wiring and a second titanium nitride film located under said first titanium nitride film, said first titanium nitride film having the composition ratio to have strong bonding force with said electrode wiring and said second titanium nitride film having the composition ratio, preventing a metal element composing said electrode wiring from diffusing into the contact area of the semiconductor device;

wherein the composition ratio of said first titanium nitride film has the proportion of the number of titanium atoms of a range from 62% to 75% for the titanium nitride; and

wherein the composition ratio of said second titanium nitride film has the proportion of the number of titanium atoms of a range from 50% to 59% for the titanium nitride.

2. The electrode structure for the semiconductor device according to claim 1:

wherein said first titanium nitride film is 500 Å

to 1,000 Å

thick; and

wherein said second titanium nitride film is of 3,000 Å

to 4,000 Å

thick.

3. An electrode structure for a semiconductor device, which is formed on the semiconductor device, consisting of silicon formed on a substrate, and for detecting a physical quantity of the substrate and converting it into an electric signal, and transferring the electric signal to the outside, comprising:

a barrier layer consisting of a high-melting metal nitride and formed on a contact area of the semiconductor;

an electrode wiring formed on the barrier layer, the barrier layer having a multilayered structure laminated with films of said high-melting metal nitride, consisting of nitrides of the same metal each having a different composition ratio from one another, said barrier layer having therein a barrier performance which prevents the metal composing said electrode wiring from diffusing into the semiconductor device, and the composition ratio of said high-melting metal nitride forming said barrier layer, being defined to have a strong bonding force with a matter bonded with said barrier layer, in at least any one of a bonding border area between said barrier layer and said electrode wiring, and a bonding border area between said barrier layer and the contact area;

wherein said high-melting metal nitride is a titanium nitride;

wherein said barrier layer has a first titanium nitride film located to contact with said electrode wiring and a second titanium nitride film located under said first titanium nitride film, said first titanium nitride film having the composition ratio to have strong bonding force with said electrode wiring and said second titanium nitride film having the composition ratio, preventing a metal element composing said electrode wiring from diffusing into the contact area of the semiconductor device; and

wherein said first titanium nitride film is 500 angstroms to 1,000 angstroms thick; and

wherein said second titanium nitride film is 3,000 angstroms to 4,000 angstroms thick.