Patents by Inventor Bernd Hupfer

Bernd Hupfer 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: 5240819
    Abstract: This invention is that of high temperature polyamides containing the hexafluoroisopropylidene group. The high temperature polyamides of the invention and photo or radiation sensitizers provide improved high temperature positive resists which can be developed in aqueous alkaline developer and thermally anneal to form heat resistant, polyoxazole relief structures suitable for use in microelectronic and printing applications. The positive photoresists of the invention have improved solubility in coating solvents and improved photospeed. The polyamides of the invention can be prepared by conventional condensation reactions; e.g. the condensation of a diamine and diacid chloride. In addition the polyamides of this invention provide high temperature protective coatings with superior adhesion properties in applications other than the photoresist area.
    Type: Grant
    Filed: March 11, 1991
    Date of Patent: August 31, 1993
    Assignee: Hoechst Celanese Corporation
    Inventors: Werner H. Mueller, Dinesh N. Khanna, Bernd Hupfer
  • Patent number: 5198325
    Abstract: A photopolymerizable mixture for producing relief structures composed of highly heat-resistant polymers is described which is composed essentially of a soluble prepolymer containing photosensitive radicals bound in an ester-like manner to carboxyl groups, monomers and a photoinitiator, wherein the photoinitiator carries at least one trihalomethyl group which reacts when exposed to light. Of advantage is the fact that, even after exposure times which are by a factor of 4 to 5 shorter compared with conventional photopolymerizable mixtures, sharp-edged resist images can be obtained with a resolution of less than 3 .mu.m.
    Type: Grant
    Filed: May 26, 1988
    Date of Patent: March 30, 1993
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Bernd Hupfer, Gerhard Buhr, Charlotte Eckes
  • Patent number: 5077378
    Abstract: This invention is that of high temperature polyamides containing the hexafluoroisopropylidene group. The high temperature polyamides of the invention and photo or radiation sensitizers provide improved high temperature positive resists which can be developed in aqueous alkaline developer and thermally anneal to form heat resistant, polyoxazole relief structures suitable for use in microelectronic and printing applications. The positive photoresists of the invention have improved solubility in coating solvents and improved photospeed. The polyamides of the invention can be prepared by conventional condensation reactions; e.g. the condensation of a diamine and diacid chloride. In addition the polyamides of this invention provide high temperature protective coatings with superior adhesion properties in applications other than the photoresist area.
    Type: Grant
    Filed: May 21, 1990
    Date of Patent: December 31, 1991
    Assignee: Hoechst Celanese Corporation
    Inventors: Werner H. Mueller, Dinesh N. Khanna, Bernd Hupfer
  • Patent number: 5021320
    Abstract: This invention is that of high temperature polyamides containing the hexafluoroisopropylidene group. The high temperature polyamides of the invention and photo or radiation sensitizers provide improved high temperature positive resists which can be developed in aqueous alkaline developer and thermally anneal to form heat resistant, polyoxazole relief structures suitable for use in microelectronic and printing applications. The positive photoresists of the invention have improved solubility in coating solvents and improved photospeed. The polyamides of the invention can be prepared by conventional condensation reactions; e.g. the condensation of a diamine and diacid chloride. In addition the polyamides of this invention provide high temperature protective coatings with superior adhesion properties in applications other than the photoresist area.
    Type: Grant
    Filed: July 7, 1989
    Date of Patent: June 4, 1991
    Assignee: Hoechst Celanese Corporation
    Inventors: Werner H. Mueller, Dinesh N. Khanna, Bernd Hupfer
  • Patent number: 4871833
    Abstract: Described are polyamic acids, at least 50 mole-% of which are comprised of recurrent units corresponding to the general formula I: ##STR1## wherein, R.sup.1 is a mono-, di-, tri- or tetranuclear aromatic group andX is O, S, CO, SO.sub.2 or CR.sup.2 R.sup.3, each one ofR.sup.2 and R.sup.3 being H or CH.sub.3.A polyamic acid of the present invention, in the form of a solution, is applied to a substrate, for example, a semiconductor device, to form a protective layer thereon, and is converted into polyimide by heating. As against comparable compounds known in the art, the polyamic acids of the present invention are distinguished by a lower inherent viscosity at an unchanged molecular weight and, consequently, by an improved processability at an equally good thermal stability.
    Type: Grant
    Filed: May 4, 1987
    Date of Patent: October 3, 1989
    Assignee: Hoechst Aktiengesellschaft
    Inventor: Bernd Hupfer