US5789818A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Structure with selective gap fill of submicron interconnects
Assignee: Texas Instruments Inc
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Filing: 1996-06-21
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Granted: 1998-08-04
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Expires: 2016-06-21
Abstract
Abstract A semiconductor device and method having a low-permittivity material between closely-spaced leads in order to decrease unwanted capacitance, while having a more structurally strong dielectric between widely-spaced leads where capacitance is not as critical. Metal layer 14 is deposited on a substrate 12 of a semiconductor wafer 10, where the metal layer 14 has a first portion 15 and a second portion 17. Widely-spaced leads 16 are formed in the first portion 15 of the metal layer 14, and a first structural dielectric layer 26 is deposited on at least the widely-spaced leads. Closely-spaced leads 18 are formed in the second portion 17 of the metal layer 14, and low-permittivity material 34 is deposited between closely-spaced leads 18. A second structural dielectric layer 36 is deposited on at least low-permittivity material 34 and closely-spaced leads 18. An advantage of the invention includes improved structural strength by placing structurally weak low-permittivity material only where needed, in areas having closely-spaced leads.
Inventors
- 👤 Robert H. Havemann
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 19:16
CPC Classifications
H; H10; H10W; H10W20/00; H10W20/40; H10W20/45; H10W20/48; H10W20/01; H10W20/071; H10W20/074; H10W20/076; H10W20/077; H10W20/098; H10W20/41; H10W20/43; H10W20/495
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
180 words
A semiconductor device comprising; a substrate having a first region and a second region; widely-spaced leads formed on said first region of said substrate, said widely-spaced leads spaced apart by more than one and one-half said minimum lead spacing; a first structural dielectric layer between said widely-spaced leads; closely-spaced leads formed on said second region of said substrate, said closely-spaced leads spaced apart by less than or equal to one and one-half said minimum lead spacing; a cavity between at least one pair of said closely-spaced leads, when said cavity is a material selected from the group consisting of air vacuum and inert gas, said cavity providing a relative dielectric constant of less than 3 between at least one pair of closely-spaced metal leads; and a second structural dielectric layer over at least said cavity and said closely-spaced leads; wherein said first structural dielectric also resides on top of said closely-spaced leads but not on said cavities, wherein said cavity extends the entire height of said closely-spaced leads and wherein said cavity extends beyond said height of said closely-spaced leads.
Claim 2
Dependent Claim
180 words
A semiconductor device comprising; a substrate having a first region and a second region; widely-spaced leads formed on said first region of said substrate, said widely-spaced leads spaced apart by more than one and one-half said minimum lead spacing; a first structural dielectric layer between said widely-spaced leads; closely-spaced leads formed on said second region of said substrate, said closely-spaced leads spaced apart by less than or equal to one and one-half said minimum lead spacing; a cavity between at least one pair of said closely-spaced leads, when said cavity is a material selected from the group consisting of air vacuum and inert gas, said cavity providing a relative dielectric constant of less than 3 between at least one pair of closely-spaced metal leads; and a second structural dielectric layer over at least said cavity and said closely-spaced leads; wherein said first structural dielectric also resides on top of said closely-spaced leads but not on said cavities, wherein said cavity extends the entire height of said closely-spaced leads and wherein said cavity extends beyond said height of said closely-spaced leads.
Claim 3
Dependent Claim
168 words
A semiconductor device comprising; a substrate having a first region and a second region; widely-spaced leads formed on said first region of said substrate, said widely-spaced leads spaced apart by more than one and one-half a minimum lead spacing; closely-spaced leads formed on said second region of said substrate, said closely-spaced leads spaced apart by less than or equal to one and one-half said minimum lead spacing; a first structural dielectric layer on top of said closely-spaced leads and between said widely-spaced leads; a cavity between at least one pair of said closely-spaced leads, herein said cavity is a material selected from the group consisting of air, vacuum and inert gas, said cavity providing a relative dielectric consisting of less than 3 between at least one pair of closely-spaced metal leads, said cavity extending the entire height of said closely-spaced leads; and a second structural dielectric layer over at least said cavity and said closely-spaced leads; wherein said first structural dielectric layer does not reside on said cavities.
Claim 4
Dependent Claim
168 words
A semiconductor device comprising; a substrate having a first region and a second region; widely-spaced leads formed on said first region of said substrate, said widely-spaced leads spaced apart by more than one and one-half a minimum lead spacing; closely-spaced leads formed on said second region of said substrate, said closely-spaced leads spaced apart by less than or equal to one and one-half said minimum lead spacing; a first structural dielectric layer on top of said closely-spaced leads and between said widely-spaced leads; a cavity between at least one pair of said closely-spaced leads, herein said cavity is a material selected from the group consisting of air, vacuum and inert gas, said cavity providing a relative dielectric consisting of less than 3 between at least one pair of closely-spaced metal leads, said cavity extending the entire height of said closely-spaced leads; and a second structural dielectric layer over at least said cavity and said closely-spaced leads; wherein said first structural dielectric layer does not reside on said cavities.
Claim 5
Dependent Claim
17 words
The semiconductor device of claim 2, wherein said cavity extends beyond said height of said closely-spaced leads.
Claim 6
Dependent Claim
178 words
A semiconductor device comprising; a substrate having a first region and a second region; widely-spaced leads formed on said first region of said substrate, said widely-spaced leads spaced apart by more than one and one-half a minimum lead spacing; a first structural dielectric layer between said widely-spaced leads; closely-spaced leads formed on said second region of said substrate, said closely-spaced leads spaced apart by less than or equal to one and one-half said minimum lead spacing; a plurality of cavities between adjacent pairs of said closely-spaced leads, wherein said cavities are materials selected from the group consisting of air, vacuum and inert gas, said cavities providing a relative dielectric constant of less than 3 between said adjacent pairs of closely-spaced meal leads; and a second structural dielectric layer over at least said cavities and said closely-spaced leads; wherein said first structural dielectric also resides on top of said closely-spaced leads but not on said cavities, wherein said cavities extend the entire height of said closely-spaced leads and wherein said cavities extend beyond said height of said closely-spaced leads.
Claim 7
Dependent Claim
178 words
A semiconductor device comprising; a substrate having a first region and a second region; widely-spaced leads formed on said first region of said substrate, said widely-spaced leads spaced apart by more than one and one-half a minimum lead spacing; a first structural dielectric layer between said widely-spaced leads; closely-spaced leads formed on said second region of said substrate, said closely-spaced leads spaced apart by less than or equal to one and one-half said minimum lead spacing; a plurality of cavities between adjacent pairs of said closely-spaced leads, wherein said cavities are materials selected from the group consisting of air, vacuum and inert gas, said cavities providing a relative dielectric constant of less than 3 between said adjacent pairs of closely-spaced meal leads; and a second structural dielectric layer over at least said cavities and said closely-spaced leads; wherein said first structural dielectric also resides on top of said closely-spaced leads but not on said cavities, wherein said cavities extend the entire height of said closely-spaced leads and wherein said cavities extend beyond said height of said closely-spaced leads.
References Cited (Backward Citations)
US5616955A
Cited
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