@article{AngelovaPenacoradaStilleretal.1994, author = {Angelova, Angelina and Penacorada, Florencio and Stiller, Burkhard and Zetzsche, Thomas and Ionov, Radoslav and Kamusewitz, Helmut and Brehmer, Ludwig}, title = {Wettability, surface morphology and stability of long chain ester multilayers obtained by different Langmuir- Blodgett deposition type}, year = {1994}, language = {en} } @article{SchulzStillerZetzscheetal.1994, author = {Schulz, Burkhard and Stiller, Burkhard and Zetzsche, Thomas and Knochenhauer, Gerald and Dietel, Reinhard and Brehmer, Ludwig}, title = {Crystal structure of 2,5-Di(4- methoxycarbonyl-phenyl)-1,3,4-oxadiazole characterized by AFM and IR- spectroscopy}, year = {1994}, language = {en} } @article{SchulzStillerZetzscheetal.1995, author = {Schulz, Burkhard and Stiller, Burkhard and Zetzsche, Thomas and Knochenhauer, Gerald and Dietel, Reinhard and Brehmer, Ludwig}, title = {Characterization of 2,5-di(p-tolyl-1,3,4- oxadiazole) crystals by IR-spectroscopy and atomic force microscopy}, year = {1995}, language = {en} } @article{HelmsReicheStilleretal.1995, author = {Helms, Andreas and Reiche, J{\"u}rgen and Stiller, Burkhard and Kobloch, H. and Brehmer, Ludwig}, title = {Herstellung d{\"u}nner organischer Schichten durch Vakuumdeposition}, year = {1995}, language = {de} } @article{PenacoradaReicheDieteletal.1996, author = {Penacorada, Florencio and Reiche, J{\"u}rgen and Dietel, Reinhard and Zetzsche, Thomas and Stiller, Burkhard and Knobloch, Harald and Brehmer, Ludwig}, title = {Monolayers and multilayers of uranyl arachidate : 2. Influence of the subphase pH on the structure and stability of Langmuir-Blodgett films}, year = {1996}, abstract = {In this second paper we describe the comprehensive structure investigations on multilayers of uranyl arachidate formed by Langmuir-Blodgett deposition from subphases of different pH on solid substrates by means of a combination of infrared spectroscopy, X-ray specular reflection, ellipsometry, and scanning force microscopy, The structure of these multilayers and their stability are obviously influenced by the subphase pH. The pH range of the acid to salt conversion determined for the Langmuir films is confirmed by the infrared spectroscopic data of the multilayers. While arachidic acid films, deposited from an uranyl acetate subphase of low pH, are found to have strongly distorted rough surface, the films of uranyl structure, The influence of the counterions on the alkyl chain conformation, chain packing, reorganization probability, and stability of the multilayer is discussed.}, language = {en} } @article{SchulzStillerZetzscheetal.1997, author = {Schulz, Burkhard and Stiller, Burkhard and Zetzsche, Thomas and Knochenhauer, Gerald and Brehmer, Ludwig}, title = {Characterization of crystals based on 1,3,4-oxadiazoles by atomic force microscopy}, year = {1997}, abstract = {The surface structures of crystals based on aromatic oxadiazoles were investigated by AFM. The crystal structure for 2,5-di(p-tolyl)-1,3,4-oxadiazole (DTO) differs from that of 2,5-di (4-methoxycarbonyl-phenyl)-1,3,4- oxadiazole (DMPO). In DMPO all molecules show parallel orientation to the surface in such a way that the surface is formed as well as by the nitrogen atoms of the heterocyclic rings and the methyl groups of the ester substituents. By contrast, the oxadiazole molecules in DTO crystals are oriented perpendicular to the crystal surface. The experimental data are interpreted by molecular modelling. It is shown that there is a difference between molecular structure of the surface, as detected by AFM, and the bulk structure determined by X-ray diffraction.}, language = {en} } @article{BrumaSavaMerceretal.1998, author = {Bruma, Maria and Sava, Ion and Mercer, Frank W. and Reddy, Victor N. and K{\"o}pnick, Thomas and Stiller, Burkhard and Schulz, Burkhard}, title = {Silicon-containing poly(amide-ether)s}, year = {1998}, abstract = {New aromatic poly(amide-ether)s (II) have been synthesized by solution polycondensation of various aromatic diamines having two ether bridges (I) with a diacid chloride containing silicon, namely bis(chlorocarbonylphenyl)- diphenyIsilane. These polymers are easy soluble in polar amidic solvents such as N-methylpyrrolidinone or dimethylformamide and can be cast into thin flexible films or coatings from such solutions. They show high thermal stability with initial decomposition temperature being above 400 °C. Their glass transition temperatures lie in the range of 220-250 °C, except for polymer He which did not show a clear Tg when heated in a differential scanning calorimetry experiment up to 300 °C. The large interval between the glass transition and decomposition temperatures of pnlymers Ia-Id could be advantageous for their processing via compression molding. The polymer coatings deposited by the spincoating, technique onto silicon wafers showed a very smooth, pinhole-free surface in atomic force microscopy investigations. The free-standing films of 20-30 mm thickness show low dielectric constant, in the range of 3.65-3.78, which is promising for future application as high performance dielectrics.}, language = {en} } @article{BrumaSchulzKoepnicketal.1998, author = {Bruma, Maria and Schulz, Burkhard and K{\"o}pnick, Thomas and Dietel, Reinhard and Stiller, Burkhard and Mercer, Frank W.}, title = {Investigation of thin films made from silicon-containing poly(phenylquinoxaline-amide)s}, year = {1998}, abstract = {Thin films in the range of 50 nm to 10 mm thickness have been prepared from NMP solutions of silicon-containing polyphenylquinoxaline-amides which had been synthesized by the polycondensation reaction of aromatic diaminophenylquinoxalines with bis(p-chlorocarbonylphenyl)diphenylsilane. A spin-coating technique onto glass plates or onto silicon wafers was used to make the film, followed by gradual heating to remove the solvent. The resulting films were very smooth and free of pinholes when studied by atomic force microscopy (AFM). They showed a strong adhesion to silicon wafers, were thermally stable in air to above 400 °C and their dielectric constant was in the range of 3.5-3.7. Thermal treatment of the films was performed in order to induce crosslinking. Such treated films became completely insoluble in organic solvents, maintained their smoothness and strong adhesion to the silicon substrate, and did not show any Tg, in DSC experiments. Their FTIR spectra in reflection mode did not show any changes compared with the untreated films, meaning on the one hand that the polymers maintain their structural integrity at high temperature and on the other hand that the number of crosslinks was very low and could not be detected by IR spectroscopy.}, language = {en} } @article{BrumaSchulzKoepnicketal.1998, author = {Bruma, Maria and Schulz, Burkhard and K{\"o}pnick, Thomas and Stiller, Burkhard and Hamciuc, Elena and Mercer, Frank W. and Cassidy, Peter}, title = {Aromatic polyamides with hexafluoroisopropylidene groups and study of the thin}, year = {1998}, language = {en} } @article{MahlerRaflerStiller1999, author = {Mahler, J. and Rafler, G. and Stiller, Burkhard}, title = {Modified melamines and melamine resins for E/Z-isomerization}, year = {1999}, language = {en} } @article{StillerKoepnickMuzikanteetal.1999, author = {Stiller, Burkhard and K{\"o}pnick, Thomas and Muzikante, I. and Neilands, O. and Utinans, M. and Dubrovich, O. and Karageorgiev, Peter and Brehmer, Ludwig}, title = {Optically induced switching effect of polymer containing indandione-1,3-pyridinium betaine side chains}, issn = {0378-2271}, year = {1999}, language = {en} } @article{GustinaMarkavaMuzikanteetal.1999, author = {Gustina, D. and Markava, E. and Muzikante, I. and Stiller, Burkhard and Brehmer, Ludwig}, title = {Photoisomerisation process of self-assembled monolayers of some novel azobenzenes}, year = {1999}, language = {en} } @article{BrumaSchulzKoepnicketal.1999, author = {Bruma, Maria and Schulz, Burkhard and K{\"o}pnick, Thomas and Stiller, Burkhard and Belomoina, Nataliya and Mercer, Frank W.}, title = {Synthesis and study of aromatic polyamides containing silicon and phenylquinoxaline rings in the main chain}, year = {1999}, abstract = {New poly(phenylquinoxaline-amide)s with silicon in the main chain have been prepared by polycondensation reaction of a diacid chloride, namely bis(p-chlorocarbonyl-phenyl)-diphenylsilane, with aromatic diamines containing one or two phenylquinoxaline rings separated by a flexible bridge such as ether or methylene. These polymers were easily soluble in polar aprotic solvents such as N-methylpyrrolidinone (NMP) and dimethylformamide (DMF) and showed high thermal stability with decomposition temperature being above 450°C and glass transition temperature in the range of 260- 304°C. Polymer solutions in NMP were processed into thin flexible films which exhibited very smooth surfaces, free of pinholes when studied by atomic force microscopy. The free-standing films showed a dielectric constant in the range of 3.6-3.7.}, language = {en} } @article{BrumaHamciucSchulzetal.1999, author = {Bruma, Maria and Hamciuc, Elena and Schulz, Burkhard and K{\"o}pnick, Thomas and Stiller, Burkhard and Mercer, Frank W.}, title = {Synthesis of fluorinated poly(phenylquinoxaline-amide)s and study of thin films made therefrom}, year = {1999}, abstract = {A series of five fluorinated poly(phenylquinoxaline-amide)s were synthesized by a polycondensation reaction of a diacid chloride containing the hexafluoroisopropylidene (6F) group, namely 2,2-bis(p-chlorocarbonylphenyl)- hexafluoropropane, with various aromatic diamines incorporating two phenyl-substituted quinoxaline rings. These polymers were easily soluble in polar aprotic solvents such as N-methylpyrrolione (NMP), dimethylformamide (DMF), and tetrahydrofurane (THF), and showed a high thermal stability with decomposition temperatures above 400 °C and glass transition temperatures in the range of 260-290 Tg. Polymer solutions in NMP were processed into free-standing films that showed low dielectric constant values, in the range of 3.4-3.9, and good mechanical properties, with tensile strength in the range of 40-80 MPa and elongation to break in the range of 22-55\%. Very thin films, in the range of tens of nanometer, which were deposited onto silicon wafers exhibited very smooth surfaces, free of pinholes when studied by atomic force microscopy (AFM).}, language = {en} } @article{BrumaSchulzKoepnicketal.1999, author = {Bruma, Maria and Schulz, Burkhard and K{\"o}pnick, Thomas and Stiller, Burkhard and Mercer, Frank W.}, title = {Study of thin films made from aromatic polyamides with silicon and phenylquinoxaline rings in the main chain}, year = {1999}, abstract = {Aromatic polyamides containing silicon and phenylquinoxaline rings in the main chain have been prepared by polycondensation reaction of a silicon-containing diacid chloride, namely bis(p-chlorocarbonylphenyl) -diphenylsilane, with various aromatic diamines having preformed phenylquinoxaline units. These polymers were easily soluble in polar aprotic solvents, such as N-methylpyrrolidinone (NMP) and dimethylformamide (DMF), and in tetrahydrofurane. They showed high thermal stability with decomposition temperature being above 450°C and glass transition temperature in the range of 253-304°C. Polymer solutions in NMP were processed into thin films having the thickness of tens of nanometer to 10 mm, by spin-coating onto glass plates or silicon wafers. The films had strong adhesion to substrates and exhibited very smooth surfaces, free of pinholes, in atomic force microscopy (AFM) studies. The free-standing films had dielectric constant in the range of 3.48-3.69. Thermal treatment of the films up to 350°C rendered them completely insoluble in organic solvents, while maintaining their smoothness and strong adhesion to the silicon substrate, and with no Tg in DSC experiments. Their FTIR spectra did not show any changes compared to the untreated films, meaning that polymers maintain their structural integrity at high temperature. {\´O} 1999 Elsevier Science S.A. All rights reserved.}, language = {en} } @article{ReicheFreydankHelmsetal.1999, author = {Reiche, J{\"u}rgen and Freydank, Anke-Christine and Helms, Andreas and Geue, Thomas and Schulz, Burkhard and Brehmer, Ludwig and Stiller, Burkhard and Knochenhauer, Gerald}, title = {Vacuum deposition films of oxadiazole compounds : formation and structure investigation}, year = {1999}, abstract = {The search for alternative routes of organic thin film formation is stimulated by the outstanding properties of these films in such fields as nonlinear optics, photonic data processing and molecular electronics. The formation of highly ordered multilayer structures by thermal vacuum deposition (VD) of organic compounds is an essential step toward the application of supramolecular organic architectures in technical systems. The VD of an amphiphilic substituted 2,5- diphenylene-1,3,4-oxadiazole 1 onto silicon substrates at defined temperature was used for the formation of ultrathin films. The structural data obtained for the VD-films of oxadiazole 1 by means of X-ray reflectivity, X-ray grazing incidence diffraction and atomic force microscopy (AFM) investigations indicate the formation of well ordered oxadiazole multilayers. The structure of the VD-multilayers is compared with that of Langmuir-Blodgett (LB) films and thermally treated LB-multilayers prepared from the same compound.}, language = {en} } @article{StrackeWendhorffGoldmannetal.2000, author = {Stracke, A. and Wendhorff, Joachim Heinz and Goldmann, Daniela and Janietz, Dietmar and Stiller, Burkhard}, title = {Gain effects in optical storage : thermal induction of a surface relief grating in a smectic liquid crystal}, year = {2000}, language = {en} } @article{KarageorgievStillerPrescheretal.2000, author = {Karageorgiev, Peter and Stiller, Burkhard and Prescher, Dietrich and Dietzel, Birgit and Schulz, Burkhard and Brehmer, Ludwig}, title = {Modification of the surface potential of azobenzene-containing langmuir-blodgett films in the near field of a scanning kelvin microscope tip by irradiation}, year = {2000}, language = {en} } @article{StillerKarageorgievPerezetal.2000, author = {Stiller, Burkhard and Karageorgiev, Peter and Perez, E. and Valez, M. and Reiche, J{\"u}rgen and Prescher, Dietrich and Dietzel, Birgit and Brehmer, Ludwig}, title = {Scanning kelvin microscopy as a tool for visualisation of optically induced molecular switching in azobenzene self assembling films}, issn = {0142-2421}, year = {2000}, language = {en} } @article{StillerKarageorgievBuchsteineretal.2003, author = {Stiller, Burkhard and Karageorgiev, Peter and Buchsteiner, Andrea and Geue, Thomas and Henneberg, Oliver and Brehmer, Ludwig and Natansohn, Almeria and Hollricher, Olga}, title = {Using light as a tool : optically Induced mass transport generated in Near-Fields}, issn = {0038-7355 -}, year = {2003}, language = {en} }