Fab Management Forum

SEMI spoke with Udo Gómez, senior vice president at Robert Bosch GmbH, about MEMS technology requirements relative to standard IC design and manufacturing. Gómez highlighted solutions to challenges of MEMS technology development and manufacturing ahead of his presentation at the 22nd Fab Management Forum at SEMICON Europa 2018, 13-16, November 2018, in Munich, Germany. To register for the event, click here.SEMI: Regarding standard processes for MEMS, the situation used to be known as the MEMS law: "one product, one process." Today, the variety of MEMS sensors and their application requirements have drastically increased. What is the status of process standardization today?Gómez: Today, standardization in MEMS is certainly not as advanced as it is for conventional semiconductor processes and model environments. However, MEMS technology has developed very much in recent years. The understanding of the numerous interactions between mechanical, chemical and electrical parameters has grown enormously. Improved process tolerances and optimized simulation tools already allow the design of standard components and their manufacture using largely standardized processes and systems.This also enables standardized MEMS process platforms in foundries for fabless suppliers, since adapting process parameters to standard designs no longer means maximum effort. But the situation changes significantly if you want to implement more powerful MEMS components for demanding applications. In this case, much effort is still required in technology development to bring new and innovative designs to mass production readiness.SEMI: How does this situation interfere with the need for a fast, market-driven product development and production ramp-up?Gómez: The constant advancement of (MEMS) technology to new limits requires enormous efforts and time. Thus, fast product cycles in consumer electronics (CE) pose particular challenges. Close interaction between product and technology development is a key success factor here, as well as a deep understanding of the cause-effect relationships. This is the only way to identify and minimize process risks at an early stage.However, the steep product ramp-ups usually required in CE also offer advantages, since learning curves are run through at much shorter time-intervals than, for example, the comparatively slow ramp-ups in the automotive industry. In this way, automotive products benefit directly from the results of CE components. Conversely, CE products benefit from the higher requirements in the automotive sector, whose technologies can be developed and tested on longer time scales.SEMI: What are the critical and different design and manufacturing requirements for MEMS products versus standard IC products, which typically run in highly standardized processes?Gómez: A very special feature of MEMS devices is their multi-physics character – mechanical, electrical, magnetic, fluidic, and even chemical and/or optical effects may play a role. This is very different from standard semiconductors. Depending on the type of sensor or actuator, dedicated and often quite sophisticated models need to be developed to ensure proper function of the device – and not least to ensure full functionality after misuse. For example, shocks or drop events are usually not relevant for standard ICs but they may be extremely relevant for MEMS devices with their fragile mechanical structures.Similarly, the influence of packaging effects like bending or thermomechanical stress may be much more significant in MEMS devices than for standard semiconductors. And last but not least, a physical/magnetic/chemical/optical … stimulus usually needs to be applied when testing MEMS devices. All of this adds complexity to the manufacturing flow and requires dedicated know-how both during the engineering stage and in mass production.SEMI: BOSCH is working to extend the process platform to include complex 3D structures. What are the advantages and benefits of using 3D structures compared to standard 2D structures? Are there 3D structured products already in mass production?Gómez: We have recently extended our well-established surface micromachining process for MEMS inertial sensors (which basically uses one functional silicon layer for the movable MEMS device) to an advanced process using a second functional micromechanical layer. This opens up a large variety of design options and allows the realization of entirely new sensor topologies. For example, our most recent z-axis accelerometers for automotive and CE applications have 3D-like structures for the movable mass.This has several advantages: Firstly, the sensors can be further miniaturized as they now have fixed electrodes for capacitive readout above and below the movable mass, i.e. a larger capacitance per area. Secondly, due to their improved symmetry, these sensors have greatly improved immunity against several parasitic effects, e.g. mechanical stress from soldering or bending on a PCB. Overall, this technology enables us to offer better performance at still very competitive product size and cost. Both automotive and CE sensors are in high volume production for different applications and customers. SEMI: What do you expect from SEMICON Europa 2018 and why do you recommend attending the Fab Management Forum?Gómez: After our very positive impressions of SEMICON Europa 2017, we are convinced that SEMICON 2018 will again meet with widespread interest within the semiconductor industry. SEMICON is an excellent opportunity for us to meet our customers and partners. The Fab Management Forum, which ideally takes place parallel to SEMICON, is a highly valuable addition for us to exchange ideas with leading industry partners and to gain new insights into current trends and technical progress. Within that context, the Forum will make a valuable contribution toward strengthening the European position in semiconductor and MEMS manufacturing. As senior vice president of Robert Bosch GmbH, Dr. Gómez heads Sensor Engineering at Bosch Automotive Electronics (AE/NE-SE) in Reutlingen, Germany, the world’s largest MEMS supplier serving the Automotive, Consumer Electronics and IoT industry. Dr. Gómez started his career at Robert Bosch GmbH in 1999 at Corporate Sector Research and Advanced Engineering (MEMS technology) after completing his doctorate in physics. Before joining Bosch Automotive Electronics in April 2018, he worked in various management positions at Bosch and also held the position of Chief Expert for MEMS sensor technology. From 2013 to March 2018, he was Chief Technical Officer of Bosch Sensortec GmbH - a fully-owned subsidiary of Robert Bosch GmbH, responsible for research and development of micro-electro-mechanical sensors (MEMS) for consumer electronics, smartphones, security systems, industrial technology and logistics.Dr. Gómez has served as Deputy Chairman of the Board of VDE/VDI-Society Microelectronics, Microsystems and Precision Engineering (GMM) since 2014 has been a member of the GSA (Global Semiconductor Alliance) EMEA Leadership Council since 2015.Serena Brischetto is a marketing and communications manager at SEMI Europe.

SEMI met with Heinz Martin Esser, managing director at Fabmatics GmbH, to discuss how existing 200mm semiconductor fabs can master the challenges of a 24x7 production under highest cost and quality pressure by implementing intralogistics automation solutions. The two spoke ahead to his presentation at the Fab Management Forum at SEMICON Europa 2018, 13-16, November 2018, in Munich, Germany. To register for the event, click here. SEMI: Looking at the latest production capacity data for 2018 – it is a 200mm fab boom. Growing demand for analog, MEMS and RF chips continues to cause acute shortages for both 200mm fab capacity and equipment. Do you think this trend will continue the next years or is it only a short term run on 200mm fabs?Esser: We at Fabmatics believe in a long-term trend. The emergence of the Internet of Things and growing digitalization in all areas of life will continue to increase demand for integrated circuits (ASICs), analog ICs, high-performance components and micro-mechanical sensors (MEMS) in the coming years. Many of these semiconductor elements should be produced in 200 mm fabs.SEMI: How does Fab automation contribute to increase capacity of existing, mature 200mm fabs?Esser: We are convinced that fab automation is one of the greatest potentials for older 200mm factories to effectively master increased demand, increasing efficiency, quality assurance and flexibility at the same time. In particular, material flow automation, which is often the missing link between existing equipment in different production areas, can help increase productivity in an elementary way.If you analyze how long valuable tools typically wait for loading and unloading, you can see a direct effect of the intralogistics automation system, which leads to a significantly higher utilization of process equipment by making the material flow independent from human performance. Additional side effects such as reduced cycle time, stable fab flow factor or flattened WIP shafts further increase the contribution of material flow automation to get the most out of existing mature factories. Older does not mean obsolete.SEMI: What are the biggest challenges for a successful implementation?Esser: There is no single challenge when you automate an existing mature fab. Instead, you face a whole variety of challenges you have to tackle, ranging from historically grown non-aligned fab layouts over non-linear material flows and older non-standardized equipment to “automation unfriendly” fab environment. Also you should not underestimate the efforts to overcome the practice manual fab operation people in the cleanroom are so familiar with for many years. Before doing automation you have to think automation, i.e. you have to question all processes to make them ready for automation.SEMI: What are the key drivers to automate a mature fab today: costs, process stability, quality or a combination of them?Esser: This question should be better asked to our customers, but we believe it is a mix of many impacts. Most likely everybody sees the cost reduction at first, but we get more aware of process and performance stability as well as quality requirements – and here our customers’ play the most important role – become more and more focused.SEMI: What do you expect from SEMICON Europa 2018 and why do you recommend attending the Fab Management Forum?Esser: This year SEMICON Europa will co-locate with electronica. So it`s going to be the greatest trade fair for electronics manufacturing in Europe. We will meet innovators and decision-makers across the whole electronics supply chain. The Fab Management Forum addresses a highly topical question that concerns all semiconductor manufacturers not only in Europe - how to handle complexity and enable the necessary flexibility to cope with customers' needs. High-ranking speakers will give an insight into the latest technologies and best practices. I am looking forward to the lively exchange with the participants and taking away new impulses for our business. Heinz Martin Esser is managing director at Fabmatics GmbH, responsible for sales and marketing, customer service and administration. He studied supply engineering at the University of Applied Sciences in Cologne and later earned a university degree in business administration. Serena Brischetto is a marketing and communications manager at SEMI Europe.