@inproceedings{FursenkoLukosiusLupinaetal.2017, author = {Fursenko, Oksana and Lukosius, Mindaugas and Lupina, G. and Bauer, Joachim and Villringer, Claus and Mai, Andreas}, title = {Development of graphene process control by industrial optical spectroscopy setup}, publisher = {SPIE}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:526-opus4-15319}, pages = {250 -- 259}, year = {2017}, abstract = {The successful integration of graphene into microelectronic devices depends strongly on the availability of fast and nondestructive characterization methods of graphene grown by CVD on large diameter production wafers [1-3] which are in the interest of the semiconductor industry. Here, a high-throughput optical metrology method for measuring the thickness and uniformity of large-area graphene sheets is demonstrated. The method is based on the combination of spectroscopic ellipsometry and normal incidence reflectometry in UV-Vis wavelength range (200-800 nm) with small light spots (~ 30 μm2) realized in wafer optical metrology tool. In the first step graphene layers were transferred on a SiO2/Si substrate in order to determine the optical constants of graphene by the combination of multi-angle ellipsometry and reflectometry. Then these data were used for the development of a process control recipe of CVD graphene on 200 mm Ge(100)/Si(100) wafers. The graphene layer quality was additionally monitored by Raman spectroscopy. Atomic force microscopy measurements were performed for micro topography evaluation. In consequence, a robust recipe for unambiguous thickness monitoring of all components of a multilayer film stack, including graphene, surface residuals or interface layer underneath graphene and surface roughness is developed. Optical monitoring of graphene thickness uniformity over a wafer has shown an excellent long term stability (s=0.004 nm) regardless of the growth of interfacial GeO2 and surface roughness. The sensitivity of the optical identification of graphene during microelectronic processing was evaluated. This optical metrology technique with combined data collection exhibit a fast and highly precise method allowing one an unambiguous detection of graphene after transferring as well as after the CVD deposition process on a Ge(100)/Si(100) wafer. This approach is well suited for industrial applications due to its repeatability and flexibility.}, language = {en} } @inproceedings{BauerHeinrichFursenkoetal.2017, author = {Bauer, Joachim and Heinrich, Friedhelm and Fursenko, Oksana and Marschmeyer, Steffen and Bluemich, Adrian and Pulwer, Silvio and Steglich, Patrick and Villringer, Claus and Mai, Andreas and Schrader, Sigurd}, title = {Very high aspect ratio through silicon via reflectometry}, series = {Proceedings of SPIE}, booktitle = {Proceedings of SPIE}, issn = {1996-756X}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:526-opus4-13758}, year = {2017}, abstract = {Through Silicon Via (TSV) technology is a key feature of new 3D integration of circuits by creation of interconnections using vias, which go through the silicon wafer. Typically, the highly-selective Bosch Si etch process, characterized by a high etch rate and high aspect ratio and forming of scallops on the sidewalls is used. As presented in this paper, we have developed an experimental setup and a respective evaluation algorithm for the control and monitoring of very high aspect ratio TSV profiles by spectroscopic reflectometry. For this purpose square via arrays with lateral dimension from 3 to 10 μm were fabricated by a Bosch etch process and analyzed by our setup. By exploiting interference and diffraction effects of waves reflected from the top and bottom surfaces as well as from the side walls of the TSV patterns, the measurements provided etch depths, CD values and scallop periods. The results were compared with data obtained by a commercial wafer metrology tool. Aspect ratios of up to 35:1 were safely evaluable by our setup.}, language = {en} } @misc{SteglichVillringerPulweretal.2017, author = {Steglich, Patrick and Villringer, Claus and Pulwer, Silvio and Dietzel, Birgit and Ksianzou, Viachaslau and Schrader, Sigurd}, title = {Chip-integrierte photonische Bauelemente}, series = {Wissenschaftliche Beitr{\"a}ge 2017}, volume = {21}, journal = {Wissenschaftliche Beitr{\"a}ge 2017}, issn = {0949-8214}, doi = {10.15771/0949-8214_2017_7}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:526-opus4-9426}, pages = {55 -- 59}, year = {2017}, abstract = {In unserer hochtechnologisierten Gesellschaft spielt die optische Daten{\"u}bertragung aufgrund der stetig wachsenden Informationsvielfalt eine immer bedeutendere Rolle. In den Anf{\"a}ngen der Nachrichtentechnik waren Datenraten von wenigen bit/s realisierbar. Heute werden mittels optischer Technologien {\"U}bertragungsraten von mehreren Gbit/s umgesetzt. M{\"o}glich wird dies durch neue Entwicklungen in der Chip-integrierten Photonik. Beispiele daf{\"u}r sind Chip-integrierte elektrooptische Modulatoren und Schalter. In diesem Artikel werden neue Entwicklungen in der Chip-integrierten Photonik diskutiert und die experimentelle Charakterisierung der Bauelemente in Form eines Ringresonators beschrieben. F{\"u}r die Experimente wird exemplarisch ein photonisches Bauelement genutzt, das aus einem hybriden Silizium-Polymer-Materialsystem besteht. Die Ergebnisse zeigen, dass diese Materialkombination vielversprechend f{\"u}r zuk{\"u}nftige Chip-integrierte photonische Bauelemente mit extrem geringem Energiebedarf ist.}, language = {de} }