US2003062610A1PendingUtilityA1
Multilayer thin film hydrogen getter
Priority: Sep 28, 2001Filed: Sep 28, 2001Published: Apr 3, 2003
Est. expirySep 28, 2021(expired)· nominal 20-yr term from priority
H10W 42/20H10W 42/276H10W 76/48Y10T428/12806Y10T428/12569Y10T428/12875Y10S428/938
33
PatentIndex Score
0
Cited by
0
References
0
Claims
Abstract
A thin film hydrogen getter is provided for protecting GaAs circuitry sealed in an hermetic package. The thin film getter which comprises a multilayer metal film which is deposited by vacuum evaporation techniques onto a surface of the packaging. The multilayer film comprises (1) a titanium film and (2) palladium film which is deposited onto the titanium film. Both the titanium and the palladium are deposited during the same coating process run, thereby preventing the titanium from being oxidized. The palladium continues to prevent the titanium from being oxidized once the getter is exposed to the atmosphere. However, hydrogen is easily able to diffuse through the palladium into the titanium where it is chemically bound up, since palladium is highly permeable to hydrogen. If EMI shielding is desired, a conductive metal, such as aluminum or copper, can first be formed between the packaging and the titanium layer.
Claims
exact text as granted — not AI-modifiedWhat is claimed is:
1 . A hydrogen getter for gettering hydrogen evolved from packaging materials employed in hermetically-sealed GaAs integrated circuitry, comprising:
(a) a layer of titanium for absorbing and chemically binding up said hydrogen, formed on a surface of said packaging; and (b) a layer of palladium for preventing oxidation of said titanium, but permeable to said hydrogen, formed on said layer of titanium.
2 . The hydrogen getter of claim 1 wherein said titanium has a total mass larger than that given by the following equation:
M
Ti
>
20
Q
eff
T
L
134
Torr
·
cm
3
·
mg
-
1
where M Ti is the mass of titanium, Q eff is the rate of hydrogen production in the package, and T L is the lifetime of the package, and wherein said palladium has a thickness of about 2,000 to 6,000 Å.
3 . The hydrogen getter of claim 1 further including a layer of an electrically conductive metal for providing electro-magnetic interference shielding, formed between said layer of titanium and said surface of said packaging.
4 . The hydrogen getter of claim 3 wherein said electrically conductive metal is selected from the group consisting of aluminum and copper.
5 . The hydrogen getter of claim 3 wherein said layer of said electrically conductive metal has a thickness ranging from 5 to 6 skin depths of wave propagation media.
6 . The hydrogen getter of claim 3 wherein said layer of said electrically conductive metal comprises aluminum and wherein said hydrogen getter further includes a layer of titanium for adhering said aluminum layer to said surface of said packaging.
7 . The hydrogen getter of claim 6 wherein said adhering layer of titanium has a thickness of about 20 nm.
8 . A method for fabricating a hydrogen getter, said hydrogen getter for gettering hydrogen evolved from packaging materials employed in hermetically-sealed GaAs integrated circuitry, said method comprising:
(a) providing said packaging; (b) vacuum-depositing a layer of titanium for absorbing and chemically binding up said hydrogen on a surface of said packaging; and (c) vacuum-depositing a layer of palladium for preventing oxidation of said titanium, but permeable to said hydrogen, on said layer of titanium, said vacuum deposition of both said titanium layer and said palladium layer being done sequentially during a single coating run to thereby prevent oxidation of said titanium layer.
9 . The method of claim 8 wherein said titanium has a total mass larger than that given by the following equation:
M
Ti
>
20
Q
eff
T
L
134
Torr
·
cm
3
·
mg
-
1
where M Ti is the mass of titanium, Q eff is the rate of hydrogen production in the package, and T L is the lifetime of the package, and wherein said palladium has a thickness of about 2,000 to 6,000 Å.
10 . The method of claim 8 further including a layer of an electrically conductive metal for providing electro-magnetic interference shielding, formed between said layer of titanium and said surface of said packaging.
11 . The method of claim 10 wherein said electrically conductive metal is selected from the group consisting of aluminum and copper.
12 . The method of claim 10 wherein said layer of said electrically conductive metal has a thickness ranging from 5 to 6 skin depths of wave propagation media.
13 . The method of claim 10 wherein said layer of said electrically conductive metal comprises aluminum and wherein said hydrogen getter further includes a layer of titanium for adhering said aluminum layer to said surface of said packaging.
14 . The method of claim 13 wherein said adhering layer of titanium has a thickness of about 20 nm.
15 . In combination, a hydrogen getter for gettering hydrogen evolved from packaging materials employed in hermetically-sealed GaAs integrated circuitry and a ground plane/electro-magnetic interference shield, comprising:
(a) a layer of an electrically conductive metal for providing electro-magnetic interference shielding, formed on a surface of said packaging; (b) a layer of titanium for absorbing and chemically binding up said hydrogen, formed on said conductive metal layer; and (c) a layer of palladium for preventing oxidation of said titanium, but permeable to said hydrogen, formed on said layer of titanium.
16 . The combination of claim 15 wherein said titanium has a total mass larger than that given by the following equation:
M
Ti
>
20
Q
eff
T
L
134
Torr
·
cm
3
·
mg
-
1
where M Ti is the mass of titanium, Q eff is the rate of hydrogen production in the package, and T L is the lifetime of the package, and wherein said palladium has a thickness of about 2,000 to 6,000 Å.
17 . The combination of claim 15 wherein said electrically conductive metal is selected from the group consisting of aluminum and copper.
18 . The combination of claim 15 wherein said layer of said electrically conductive metal is formed to a thickness ranging from 5 to 6 skin depths of wave propagation media.
19 . The combination of claim 15 wherein said layer of said electrically conductive metal comprises aluminum and wherein said combination further includes a layer of titanium for adhering said aluminum layer to said surface of said packaging.
20 . The combination of claim 19 wherein said adhering layer of titanium is formed to a thickness of about 20 nm.
21 . A method for fabricating a combination of a hydrogen getter for gettering hydrogen evolved from packaging materials employed in hermetically-sealed GaAs integrated circuitry and a ground plane/electro-magnetic interference shield, said method comprising:
(a) providing said packaging; (b) forming a layer of an electrically conductive metal for providing electro-magnetic interference shielding, formed on a surface of said packaging; (c) vacuum-depositing a layer of titanium for absorbing and chemically binding up said hydrogen, formed on said conductive metal layer; and (d) vacuum-depositing a layer of palladium for preventing oxidation of said titanium, but permeable to said hydrogen, formed on said layer of titanium.
22 . The method of claim 21 wherein said titanium has a total mass larger than that given by the following equation:
M
Ti
>
20
Q
eff
T
L
134
Torr
·
cm
3
·
mg
-
1
where M Ti is the mass of titanium, Q eff is the rate of hydrogen production in the package, and T L is the lifetime of the package, and wherein said palladium has a thickness of about 2,000 to 6,000 Å.
23 . The combination of claim 21 wherein said layer of said electrically conductive metal is formed to a thickness ranging from 5 to 6 skin depths of wave propagation media.
24 . The combination of claim 21 wherein said electrically conductive metal is selected from the group consisting of aluminum and copper.
25 . The combination of claim 24 wherein said layer of said electrically conductive metal comprises aluminum and is vacuum-deposited and wherein said combination further includes vacuum-depositing a layer of titanium for adhering said aluminum layer to said surface of said packaging.
26 . The combination of claim 25 wherein said adhering layer of titanium is deposited to a thickness of about 20 nm.
27 . The combination of claim 24 wherein said layer of said electrically conductive metal comprises copper and is electroless-deposited on said surface of said packaging.Join the waitlist — get patent alerts
Track US2003062610A1 — get alerts on status changes and closely related new filings.
We store only your email — no account needed. See our privacy policy.