Enhanced performance of polymer waveguides by replication and uv-patterning in ORMOCER

Recent results on waveguide device fabrication by replication of inorganic copolymers (ORMOCERs) are presented. The use of optimized ORMOCER resins offers advantages over conventional organic polymers. The organic as well as inorganic crosslinking is responsible to high thermal and chemical stability and thus an improved stability of the waveguide devices. Fluorination of ORMOCER side chains reduces the NIR absorption to <0.1 dB/cm at 1.55 mu m and <0.3 dB/cm at 1.3 mu m. Furthermore, the synthesis of purely inorganically crosslinking CH-free ORMOCER is possible. The refractive index can be turned so that highly fluorinated core material can be combined with low-cost unfluorinated cladding material. The influence of the sidewall roughness of replication tools on scattering losses is investigated, and methods to fabricate smooth original structures have been developed leading to an additional scattering loss <O. 1 dB/cm in single-mode strip waveguides even at visible wavelengths. Furthe rmore, an improved deforming behaviour is achieved. UV-patterning by uv-induced crosslinking is a second waveguide fabrication method used in ORMOCERs in thermooptical switching nodes are discussed

Inorganic-organic hybrid materials for application in optical devices

Integrated passive and active optical devices are the key components in current and future data transfer technologies. In order to fulfill future requirements in miniaturization for diffractive, refractive and integrated optical devices, new materials with higher thermal stability and a better compatibility to processing techniques used in conventional semiconductor devices production are needed. Inorganic-organic hybrid polymers (ORMOCER((R))s) produced at fairly low costs with a high degree of reproducibility are now proven candidates. The materials can be functionalized such that their physical and chemical properties can be tailored towards, e.g. optical applications on wafer-scale such as waveguides, gratings or microoptical devices. The materials behave as a negative resist and can thus be patterned by UV exposure with good resolution. Besides, the materials are very well suited for thin and thick film packaging technology. We here particularly focus on materials for optical (telecom/microoptics) applications. The optical behavior is characterized and discussed with respect to the chemical functionalities. Additionally, some application examples of selected optical components are given, produced either by UV lithography or by replication technology.close10610

Translocator Protein (TSPO) Expression in Platelets of Depressed Patients Decreases during Antidepressant Therapy

Introduction: A promising candidate in the field of pharmacological treatment options regarding major depressive disorder (MDD) is the mitochondrial translocator protein (18 kDa) (TSPO). TSPO is crucial for neurosteroid synthesis, which is in turn important for the regulation of emotions. It has already been shown that TSPO expression in platelets of depressed patients is reduced compared to healthy subjects. Methods: We measured TSPO levels in platelets of 37 depressed patients before and after 6 weeks of pharmacological treatment to test the hypotheses that i) such treatment would increase TSPO expression and ii) that this increase would be correlated with therapeutic response. Results: Surprisingly, TSPO levels in platelets of all patients were significantly reduced after 6 weeks of treatment (p=0.044). Within the responder group, a non-significant trend towards greater TSPO level reduction could be observed. Discussion: These results challenge our hypotheses that TSPO levels might increase during antidepressant therapy along with a decrease in depressive symptoms. Thus, we assume that TSPO expression in platelets is not a suitable state marker for MDD

Photonik II - Optische Verbindungstechnik (Komponenten und Subsysteme). Teilvorhaben: 4x4 Raumschaltmatrix in Polymeren Abschlussbericht

Recent results on waveguide device fabrication by replication of inorganic-organic copolymers (ORMOCERs) are presented. The use of optimized ORMOCER resins offers advantages over conventional organic polymers. The organic as well as inorganic crosslinking is responsible to high thermal and chemical stability and thus an improved stability of the waveguide devices. Fluorination of ORMOCER side chains reduces the NIR absorption to &lt;0.4 dB/cm at 1.55 #mu#m and &lt;0.3 dB/cm at 1.3 #mu#m. Furthermore, the synthesis of purely inorganically crosslinked CH-free ORMOCER is possible. The refractive index can be tuned so that highly fluorinated core material can be combined with low-cost unfluorinated cladding material. The influence of the sidewall roughness of replication tools on scattering losses is investigated, and methods to fabricate smooth original structures have been developed leading to an additional scattering loss &lt;0.1 dB/cm in single-mode strip waveguides even at visible wavelengths. Furthermore, an improved deforming behavior is achieved. UV-patterning by uv-induced crosslinking is a second waveguide fabrication method used in ORMOCER. Applications of ORMOCERs in thermooptical switching nodes are discussed. (orig.)SIGLEAvailable from TIB Hannover: DtF QN1(74,28) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekBundesministerium fuer Bildung, Wissenschaft, Forschung und Technologie, Bonn (Germany)DEGerman