Patents by Inventor Ludo Deferm

Ludo Deferm has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 6380039
    Abstract: A scaleable device concept and particularly a method for fabrication thereof is disclosed, which allows for a minimal well-controlled gate overlap by using low resistivity source/drain extension regions with shallow junctions. By using such shallow junctions, which are obtained using L-shaped spacers, the gate overlap is no longer dependent on the junction depth of the source/drain contact regions. Particularly the L-shaped spacers are used to locally reduce the penetration depth of the source/drain implantation in the substrate. This concept is particularly interesting for FET's having a channel length below 0.25 &mgr;m because this approach broadens the process window of the silicidation process of the source/drain contact regions. Moreover, the extension regions have to be subjected only to a limited thermal budget.
    Type: Grant
    Filed: April 1, 1999
    Date of Patent: April 30, 2002
    Assignee: Interuniversitair Microelektronica Centrum (IMEC VZW)
    Inventors: Goncal Badenes, Ludo Deferm, Stephan Beckx, Serge Vanhaelemeersch
  • Patent number: 6282124
    Abstract: The present invention is a method for programming SSI cells or an array of said cells. The method achieves very fast programming while consuming only a very small amount of power, which paves the way for new applications such as battery-operated systems, page-mode programming for very high data throughput. The method also allows for the bitline voltage to be increased internally on the chip in order to circumvent the efficiency decrease associated with supply voltage scaling. By exploring the SSI mechanism in the subthreshold regime, an optimum value for the CG voltage is found for which the gate current is no longer maximized, but the energy consumed from the power supply is minimized and the injection efficiency during programming is maximized. The programming of a memory cell in this regime, where the gate current is a very steep function of the CG voltage, is, however, still achieved in a few microseconds while consuming only a very small cell current in the range of nanoamperes.
    Type: Grant
    Filed: June 7, 1999
    Date of Patent: August 28, 2001
    Assignee: Interuniversitair Microelektronica Centrum (IMEC, vzw)
    Inventors: Jan F. Van Houdt, Luc Haspeslagh, Ludo Deferm, Guido Groeseneken, Herman Maes
  • Publication number: 20010012668
    Abstract: A scaleable device concept and particularly a method for fabrication thereof is disclosed, which allows for a minimal well-controlled gate overlap by using low resistivity source/drain extension regions with shallow junctions. By using such shallow junctions, which are obtained using L-shaped spacers, the gate overlap is no longer dependent on the junction depth of the source/drain contact regions. Particularly the L-shaped spacers are used to locally reduce the penetration depth of the source/drain implantation in the substrate. This concept is particularly interesting for FET's having a channel length below 0.25 &mgr;m because this approach broadens the process window of the silicidation process of the source/drain contact regions. Moreover, the extension regions have to be subjected only to a limited thermal budget.
    Type: Application
    Filed: April 1, 1999
    Publication date: August 9, 2001
    Inventors: GONCAL BADENES, LUDO DEFERM, STEPHAN BECKX, SERGE VANHAELEMEERSCH
  • Patent number: 6255227
    Abstract: The present invention relates to methods for controlling the etching rate of CoSi2 layers by adjusting the pH of an HF-based solution to obtain the desired etch rate. The pH of the HF-based solution may be adjusted by adding pH modifying chemicals to the solution. A further aspect of the invention is an improved method for manufacturing Schotky barrier infared detectors employing the controlled etching step. A method for reducing drain induced barrier lowering in an active transistor having a small gate length is also provided.
    Type: Grant
    Filed: January 6, 2000
    Date of Patent: July 3, 2001
    Assignee: Interuniversitair Microelektronica Centrum
    Inventors: Ricardo Alves Donaton, Karen Irma Josef Maex, Rita Verbeeck, Philippe Jansen, Rita Rooyackers, Ludo Deferm, Mikhail Rodionovich Baklanov
  • Patent number: 6153484
    Abstract: The present invention relates to methods for controlling the etching rate of CoSi.sub.2 layers by adjusting the pH of an HF-based solution to obtain the desired etch rate. The pH of the HF-based solution may be adjusted by adding pH modifying chemicals to the solution. A further aspect of the invention is an improved method for manufacturing Schottky barrier infared detectors employing the controlled etching step. A method for reducing drain induced barrier lowering in an active transistor having a small gate length is also provided.
    Type: Grant
    Filed: June 19, 1996
    Date of Patent: November 28, 2000
    Assignee: IMEC VZW
    Inventors: Ricardo Alves Donaton, Karen Irma Josef Maex, Rita Verbeeck, Philippe Jansen, Rita Rooyackers, Ludo Deferm, Mikhail Rodionovich Baklanov
  • Patent number: 6071825
    Abstract: The present invention relates to methods for fabricating Fully Overlapped Nitride-Etch Defined (Fond) devices. These methods permit the lateral dimension and depth of the lowly-doped source and drain extensions to be independently controlled and well defined.
    Type: Grant
    Filed: December 4, 1997
    Date of Patent: June 6, 2000
    Assignee: InterUniversitaire Microelektronica Centrum (IMEC VZW)
    Inventor: Ludo Deferm
  • Patent number: 6044015
    Abstract: The present invention is a method for programming SSI cells or an array of said cells. The method achieves very fast programming while consuming only a very small amount of power, which paves the way for new applications such as battery-operated systems, page-mode programming for very high data throughput. The method also allows for the bitline voltage to be increased internally on the chip in order to circumvent the efficiency decrease associated with supply voltage scaling. By exploring the SSI mechanism in the subthreshold regime, an optimum value for the CG voltage is found for which the gate current is no longer maximized, but the energy consumed from the power supply is minimized and the injection efficiency during programming is maximized. The programming of a memory cell in this regime, where the gate current is a very steep function of the CG voltage, is, however, still achieved in a few microseconds while consuming only a very small cell current in the range of nanoamperes.
    Type: Grant
    Filed: August 9, 1996
    Date of Patent: March 28, 2000
    Assignee: Imec vzw
    Inventors: Jan F. Van Houdt, Luc Haspeslagh, Ludo Deferm, Guido Groeseneken, Herman Maes
  • Patent number: 5969991
    Abstract: The present invention is a method for programming SSI cells or an array of said cells. The method achieves very fast programming while consuming only a very small amount of power, which paves the way for new applications such as battery-operated systems, page-mode programming for very high data throughput. The method also allows for the bitline voltage to be increased internally on the chip in order to circumvent the efficiency decrease associated with supply voltage scaling. By exploring the SSI mechanism in the subthreshold regime, an optimum value for the CG voltage is found for which the gate current is no longer maximized, but the energy consumed from the power supply is minimized and the injection efficiency during programming is maximized. The programming of a memory cell in this regime, where the gate current is a very steep function of the CG voltage, is, however, still achieved in a few microseconds while consuming only a very small cell current in the range of nanoamperes.
    Type: Grant
    Filed: June 2, 1997
    Date of Patent: October 19, 1999
    Assignee: Interuniversitair Micro-Elektronica Centrum VZW
    Inventors: Jan F. Van Houdt, Luc Haspeslagh, Ludo Deferm, Guido Groeseneken, Herman Maes