← Back to Patent Explorer
US4447289A Expired / Lapsed US ⏱️ 0.0 years remaining

Process for the manufacture of coarsely crystalline to monocrystalline sheets of semiconductor material

Assignee: HELIOTRONIC FORSCHUNGS-UND ENTWICKLUNGSGESELLSCHAFT fur
•
Filing: 1982-07-12
•
Granted: 1984-05-08
•
Expires: 2002-07-12
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract The invention provides a process for the manufacture of coarsely crystalline to monocrystalline sheets and/or plates of semiconductor material of preferred orientation. A meniscus of molten semiconductor material comes in contact with a moving, cooler substrate of the same coarsely crystalline to monocrystalline semiconductor material, during which, while transferring the preferred orientation, a thin sheet of the semiconductor material is pulled onto the substrate and, after cooling, becomes detached from the substrate. The substrate can be reused as often as desired.

Inventors

  • 👤 Joachim Geissler
  • 👤 Dieter Helmreich

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-28 02:39
CPC Classifications
H; H10; H10F; H10F71/00; H10F71/121; C; C30; C30B; C30B15/00; C30B15/06; C30B15/36; C30B33/00; H10F71/1221; Y; Y02; Y02E; Y02E10/00; Y02E10/50; Y02E10/546; Y02E10/547; Y02P; Y02P70/00; Y02P70/50; Y10; Y10S; Y10S117/00; Y10S117/914; Y10S117/915

Claims Analysis

Total Claims: 7
Claim 1
Independent Claim 125 words
In a process for the manufacture of coarsely crystalline to monocrystalline sheets of semi-conductor material of preferred orientation by applying molten semiconductor material to a substrate with subsequent controlled solidification and subsequent automatic release of the applied semiconductor material, the improvement comprising the steps of: bringing molten semiconductor material into contact with a substrate of the same semiconductor material having the desired coarsely crystalline to monocrystalline structure, said substrate being guided past the point of contact at a speed of at least 75 mm/s; and maintaining the substrate at a temperature of not more than 0.8 T M , where T M denotes the melting point of the semiconductor material expressed in degress Kelvin, so as to ensure the automatic release of the growing sheet.
Claim 2
Dependent Claim 125 words
In a process for the manufacture of coarsely crystalline to monocrystalline sheets of semi-conductor material of preferred orientation by applying molten semiconductor material to a substrate with subsequent controlled solidification and subsequent automatic release of the applied semiconductor material, the improvement comprising the steps of: bringing molten semiconductor material into contact with a substrate of the same semiconductor material having the desired coarsely crystalline to monocrystalline structure, said substrate being guided past the point of contact at a speed of at least 75 mm/s; and maintaining the substrate at a temperature of not more than 0.8 T M , where T M denotes the melting point of the semiconductor material expressed in degress Kelvin, so as to ensure the automatic release of the growing sheet.
Claim 3
Dependent Claim 26 words
The process of claim 1, wherein said molten semiconductor material and the substrate are brought into contact with one another by means of a melt meniscus.
Claim 4
Dependent Claim 22 words
The process of claim 2, wherein said meniscus of said molten semiconductor material is produced with the aid of a slot-like aperture.
Claim 5
Dependent Claim 25 words
The process of claim 1, wherein said melt of semiconductor material is maintained at a temperature of at least 5° C. above its melting point.
Claim 6
Dependent Claim 28 words
The process of claim 1, additionally including the step of regulating the thickness of the sheet of semiconductor material by appropriate adjustment of the speed of the substrate.
Claim 7
Dependent Claim 13 words
The process of claim 1, wherein silicon is used as said semiconductor material.

References Cited (Backward Citations)

US4119744A Cited
US4113548A Cited
US4233338A Cited
US4366024A Cited
US4309239A Cited
US4303463A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1987-05-08 1987-11-07 1988-05-08 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1991-05-08 1991-11-07 1992-05-08 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1995-05-08 1995-11-07 1996-05-08 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag