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The wafer backside grinding process has been a crucial technology to realize multi-layer stacking and chip performance improvement in the three dimension integrated circuits (3D IC) manufacturing. The total thickness variation (TTV) control is the bottleneck in the advanced process. However, the quantitative analysis theory model and adjustment strategy for TTV control are not currently available. This paper developed a comprehensive simulation model based on the optimized grinding tool configuration, and several typical TTV shapes were obtained. The relationship between the TTV feature components and the spindle posture was established. The linear superposition effect of TTV feature components and a new formation mechanism of TTV shape were revealed. It illustrated that the couple variation between the two TTV feature components could not be eliminated completely. To achieve the desired wafer thickness uniformity through a concise spindle posture adjustment operation, an effective strategy for TTV control was proposed. The experiments on TTV optimization were carried out, through which the developed model and TTV control strategy were verified to play a significant role in wafer thickness uniformity improvement. This work revealed a new insight into the fine control method to the TTV optimization, and provided a guidance for high-end grinding tool and advanced thinning process development.

To date, the most common method for setting the magic angle in magic angle spinning (MAS) solid state NMR experiments has been to monitor the NMR signal from a quadrupolar nuclide (such as 79Br in KBr) under MAS, then swapping to a sample of interest. Here we introduce the use of single crystal sapphire rotors as a new method to set the magic angle while spinning a sample of interest. Using both simulations and experiment, we show that the 27Al satellite transitions for a single crystal sapphire rotor spinning about its crystalline c-axis manifest off magic angle as fve resonances that coalesce into three peaks with maximum intensity at the magic angle. The difference in frequency between the satellite transitions can be used to measure the offset from the magic angle with high precision., Journal of Magnetic Resonance Open, 8-9, ISSN:2666-4410

Precise alignment of the sample’s spinning axis is vital for many magic angle spinning solid state NMR experiments. Spherical rotors are a new paradigm for magic angle spinning NMR, having been demonstrated to spin stably with little risk of rotor crash, but like cylindrical rotors, they have previously only utilized a mechanical adjustment method to set the sample’s rotation axis to the magic angle. Here we show that by using a second gas aperture within the stator, a spherical rotor’s axis of rotation may be precisely pitched about the magic angle without mechanical adjustment or motion of the stator. The 2H MAS sideband lineshape of the carboxylic acid deuteron resonance in d4-malonic acid is used as a measure of the rotor’s absolute deviation above or below the magic angle by comparing the experimental data to simulated lineshapes. We observe a linear, monotonic relationship between the angle adjustment gas flow rate and the rotor’s pitch angle, which is also accompanied by an increase in spinning rate. Precise and in operando control of the spinning axis angle is expected to have considerable advantages to future implementation of MAS within narrow-bore magnets, and for variable angle spinning (VAS) and dynamic angle spinning (DAS) experiments., Journal of Magnetic Resonance, 6–7, ISSN:1090-7807

The aim of this article is to analyse the involute gear of a ship´s gear pump. The gear applied in a direct gear is usually designed to comply with requirements for sustainability, reliability and operability under unfavourable working conditions. These requirements can be achieved by adjusting the axis distance, angular correction, as well as by rearranging the pressure angle. These modifications are directly interconnected.

Die mikrometergenaue Lagejustierung von Koppelelementen zu Lichtwellenleitern in elektro-optischen Leiterplatten ist bislang nur mit hohem manuellem Aufwand im Labor umsetzbar. In diesem Beitrag wird ein neu entwickeltes hochgenaues Handlingsystem vorgestellt, das neben der mikrometergenauen bauteilindividuellen Lagerfassung eine dreidimensionale Feinpositionierung und zusätzlich eine greiferintegrierte Winkelfeinstellung am gegriffenen Bauteil ermöglicht.

Für die hochgenaue Lagezuordnung von Mikrobauteilen in Mikromontageprozessen fehlen bislang Lösungen für eine greifernahe oder greiferintegrierte Winkelfeinstellung. In der vorliegenden Arbeit werden Einflussfaktoren und Auswirkungen lokaler Restfehler auf die Lagezuordnung im Mikromontageprozess diskutiert und Strategien für eine Lagekorrektur am Mikrobauteil unmittelbar im Montageprozess abgeleitet. Im Mittelpunkt steht die Herleitung und Erforschung eines kinematischen Grundprinzips für eine greiferintegrierte Winkelfein- stellung. Eine durch Simulation des Verformungsverhaltens optimierte räumliche Biegegelenk- struktur gestattet das spielfreie Einstellen und Halten kleinster Winkellagen im Winkel- sekundenbereich um einen auf dem gegriffenen Bauteil liegenden Drehpunkt. Das Funktions- prinzip dieses Übertragungsgliedes bildet die Grundlage für einen neuartigen modular aufgebauten Präzisionsgreifertyp. Die Wirksamkeit der greiferintegrierten Winkelfein- stellung wird an einem Anlagendemonstrator zur hochgenauen Bestückung optischer Leiter- platten mit elektrisch-optischen Sende- und Empfangsmodulen nachgewiesen. Mithilfe des neu entwickelten modularen Präzisionsgreifers lassen sich Mikromontagestrategien mit prozessintegrierter bauteilindividueller Lagekorrektur umsetzen. Montagegenauigkeiten unter 5 µm können damit besser anlagentechnisch beherrscht werden, ohne dass ein zusätzliches manuelles Feinausrichten notwendig ist. For state-of-the-art micro assembly processes with high precision alignment of micro components, solutions for a precise angle adjustment near by or integrated into a gripper are not provided yet. In this PhD thesis influencing factors and implications of local alignment failures are will be discussed and correction strategies directly in the assembling flow are will be deduced. In the central point of the PhD thesis the derivation and investigation of a novel kinematic principle for a gripper integrated angle adjustment are located. A flexure hinge structure could be designed that enables a free from backlash adjusting and fixing of angles in a size of less angular seconds whereas the center of rotation is located on the gripped part. The hinge structure was optimized by simulating the deformation behavior. The functional principle of this mechanism presents the base of a novel type of a modular precision gripper. The effectivity of the gripper integrated angle adjustment was verified at the application of high precision mounting of electric-optical circuit boards with light coupling transmitter and receiver modules. With the help of the new developed precision gripper micro assembly strategies could be realized basing on in-process alignment corrections of the individual gripped micro part. Assembly accuracies below 5 microns could be achieved plantspecific in a better way without additional manual steps for fine positioning.

The accurate alignment of electric-optical modules in front of buried wave-guides in optical printed circuit boards presents a new field of ambitious micro-assembly tasks. A micro-actuated precision gripper with an integrated tilt function is the key component of a highest precision assembly system. The symmetrical arrangement A micro-actuated precision gripper with an integrated tilt function is the key component of a highest precision assembly system. The symmetrical arrangement A micro-actuated precision gripper with an integrated tilt function is the key component of a highest precision assembly system. The symmetrical arrangement of solid state joints enables circular movement around a point outside the structure without additional guide elements over an angle range of ± 2°. This article describes the realized way of solution and demonstrates the results of the first test program. The methodology of accurate angle adjustment is applicable to future modular machining systems with highest precision.