23 entries, filtered by: Wafer Manufacturing
Published: December 2012

The fabrication of semiconductor devices, even in the area of customer oriented business, is one of the most complex production tasks in the world. A typical wafer production process consists of several hundred steps with numerous resources like equipments and operating staff. The optimal assignment of each resource at each time for a certain number of wafers is vital for a efficient production process. Several demands defined by the customers and facility management must be taken into consideration with the objective to find the best tradeoff between the different needs.


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Published: October 2012

State of the art polymer strippers were identified and successfully evaluated as interesting alternatives as CMOS-compatible wet activations for semiconductor wafer direct bonding processes, including both high and low temperature annealing for bond interface strengthening. The polymer strippers achieve both excellent surface cleaning and wafer bonding activation by hydrophilization and are therefore a very interesting alternative as semiconductor direct wafer bonding pre-treatment.


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Published: October 2012

Hermetic sealing is important regarding functionality and reliability for MEMS components. Typically this sealing is done on the wafer level using wafer bonding which simultaneously also provides mechanical protective caps. However, inner pressure and hermeticity testing and monitoring a still a critical issue; therefore, in this paper a test structure adapted to a MEMS foundry process for inertial sensors is introduced.


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Published: September 2012

Gate oxide early breakdown was investigated. It was verified that the gate oxide quality is good and failure was due to extrinsic causes. The failure, which was localized at the edge of LOCOS was similar to Kooi effect. However, investigations showed that it was due to nitridation occured during high temperature nitrogen anneal. Investigation methods to find the root cause of failure were explained. Alternative methods to solve the failure were explored; including thickening the sacrificial oxide layer and changing the nitrogen anneal process sequence. Final solution was chosen based on PCM stress test, QBD and TDDB result with minimal process change.


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Published: April 2012

In a typical ASIC semiconductor facility, there are hundreds of products processed on dozens of different equipments with unequal characteristics. Sequence depended equipment setups, failures, preventive maintenance and product specific re-entrant flows cause a high variability in factory performance measures. Also different customer demands, which are natural in the foundry business, should be taken into account (e.g. delivery dates or throughput). To reduce the variability and to improve the factory performance a robust and efficient dispatching and scheduling strategy is vital.


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Published: April 2012

Inline defect control systems are used across the semiconductor industry for detection of process failures like equipment issues or yield problems. Besides to the goal to improve the yield of each process, it may have a negative influence on factory performance as well. The measurement of all lots in all defect control monitors of a process is not feasible, even when there are bottleneck situations.


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Published: December 2011

Based on specific technology flows, various surface layers are bonded by glass frit wafer bonding. In this paper, the behaviour of typical layers, such as TEOS, Nitride and thermal oxide, and their effect on the bonding results are introduced.


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Published: December 2011

Looking for new improvement options such as new dispatching rules of an existing semiconductor fabrication facility, a detailed model is indispensable to check the data quality as well as detecting main influences of the facility and finally testing the new optimization approaches. In this paper, the whole way is described starting from the data acquisition and finishing with a appropriate model. In this study the modeling tool AnyLogic 6 is used. The model generation process show how important a reliable factory database is and shows first appendages of automated model generation. An other important fact presented is the verification of the model according to real factory performance indicators.


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Published: November 2011

The purpose of this paper is to study the order management flow currently implemented in supply chain of a semiconductor industry. There are various activities involved in a supply chain ranging from providing raw materials to the production of products, and also to ensure the delivery of the end products to customers. The main focus of a supply chain is to ensure that customers' orders are well-managed from the first day when the order is placed until the last day when the end products are ready to be delivered to customers. In other words, order fulfillment process (OFP) has to be practiced every time when customers place order.


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Published: September 2011

For the Synchronous DC-DC converter switching performance of low-voltage power MOSFETs, the gate-drain charge density (Qgd) is an important parameter. The so-called figure-of-merit, which is defined as the product of the specific on-resistance (Ron.sp) and Qgd is commonly used to quantify the switching performance for a specified off-state breakdown voltage (BVds).


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