US4319119A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for gettering semiconductor components and integrated semiconductor circuits
Assignee: Siemens AG
•
Filing: 1979-06-25
•
Granted: 1982-03-09
•
Expires: 1999-06-25
Abstract
Abstract Semiconductor components and integrated semiconductor circuits which are produced in a semiconductor crystal wafer are provided with a getter layer on the back side (opposite the active device side) of a semiconductor crystal wafer by controllably irradiating such back side with laser light pulses.
Inventors
- 👤 Hartmut Runge
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 20:28
CPC Classifications
H; H10; H10P; H10P34/00; H10P34/40; H10P34/42; H10P36/00; H10P36/03; Y; Y10; Y10S; Y10S148/00; Y10S148/165; Y10S438/00; Y10S438/94
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
147 words
In a process for gettering semiconductor components and integrated semiconductor circuits whose structures are produced in monocrystalline semiconductor material wafers wherein gettering areas are provided on a back side of such wafer, the improvement comprising: controllably irradiating select areas of a back side of a monocrystalline semiconductor material wafer with laser light pulses so as to produce dislocation networks in the irradiated areas, said laser irradiation being controlled in such a manner that at least two laser pulses are irradiated onto said select areas of the wafer, a first laser pulse being of sufficient energy to evaporate a relatively thin layer of material from the irradiated areas and a second laser pulse being of sufficient energy to produce dislocation networks in the irradiated areas, said first laser pulse having an energy level which is higher by a factor of 2 than that of said second layer pulse.
Claim 2
Dependent Claim
147 words
In a process for gettering semiconductor components and integrated semiconductor circuits whose structures are produced in monocrystalline semiconductor material wafers wherein gettering areas are provided on a back side of such wafer, the improvement comprising: controllably irradiating select areas of a back side of a monocrystalline semiconductor material wafer with laser light pulses so as to produce dislocation networks in the irradiated areas, said laser irradiation being controlled in such a manner that at least two laser pulses are irradiated onto said select areas of the wafer, a first laser pulse being of sufficient energy to evaporate a relatively thin layer of material from the irradiated areas and a second laser pulse being of sufficient energy to produce dislocation networks in the irradiated areas, said first laser pulse having an energy level which is higher by a factor of 2 than that of said second layer pulse.
Claim 3
Dependent Claim
32 words
In a process as defined in claim 1 wherein said first laser pulse has sufficient energy to evaporate a layer having a thickness in the range of about 0.5 to 10 μm.
Claim 4
Dependent Claim
30 words
In a process as defined in claim 1 wherein said second laser pulse has sufficient energy to produce a getter layer having a thickness of about 0.5 to 10 μm.
Claim 5
Dependent Claim
27 words
A process as defined in claim 3 wherein said second laser pulse has sufficient energy to produce a getter layer having a thickness of about 1 μm.
Claim 6
Dependent Claim
25 words
A process as defined in claim 1 wherein said wafer is composed of silicon and said laser light pulses are generated from a ruby laser.
Claim 7
Dependent Claim
38 words
A process as defined in claim 1 wherein said laser light pulses have an energy density in the range of about 1 to 10 joule/cm 2 and said pulse have a duration of about 10 to 50 ns.
Claim 8
Dependent Claim
115 words
A process for producing a gettering layer on semiconductor components and on integrated semiconductor circuits whose structures are produced in monocrystalline semiconductor material wafers comprising: controllably irradiating a back surface of such wafers with a first laser light pulse having sufficient energy to evaporate a relatively thin layer of material from said surface so as to produce a fresh surface; and controllably irradiating the fresh surface of such wafer with a second laser light pulse having sufficient energy to produce a relatively thin layer of dislocation network, said first laser light pulse having an energy density which is higher by a factor of about 2 than the energy density of said second laser light pulse.
Claim 9
Dependent Claim
115 words
A process for producing a gettering layer on semiconductor components and on integrated semiconductor circuits whose structures are produced in monocrystalline semiconductor material wafers comprising: controllably irradiating a back surface of such wafers with a first laser light pulse having sufficient energy to evaporate a relatively thin layer of material from said surface so as to produce a fresh surface; and controllably irradiating the fresh surface of such wafer with a second laser light pulse having sufficient energy to produce a relatively thin layer of dislocation network, said first laser light pulse having an energy density which is higher by a factor of about 2 than the energy density of said second laser light pulse.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-03-08 | 1985-09-07 | 1986-03-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-03-08 | 1989-09-07 | 1990-03-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-03-08 | 1993-09-07 | 1994-03-09 | $7700.00 | Window Closed / Lapsed |