TechBlog of Fraunhofer ISIT

In order to extend the know-how on the topic of thick wire bonding of power semiconductor devices on FR4 substrates at ISIT, a feasibility study for a thick wire bonding process with 500µm Al thick wire was carried out as part of a microtechnologist's final thesis. Shear tests and cross-section analyses were used to evaluate the bonded joints for shear strength and crack formation.

As mobile robotic systems become more autonomous, the number of sensors increases, the effort required to link their data increases, and with it the need for computing power to realize reliable and safe real-time operation. Architecture scalability, sufficient transmission bandwidth between sensor and data processing, and minimization of power requirements are the main challenges for the development of high-performance computers to be used in mobile systems. It is predicted that in less than 10 years, the required computing capacity in the sensor periphery will have to match that of a supercomputer today. This requirement can only be met by a combination of hardware and software components specifically developed for each other.

Fraunhofer researchers have set themselves the task of supplying networked sensors with sufficient energy and storing the energy locally. The result is a variety of novel components.

Producing functional samples or prototypes of miniaturized electro-optical systems can be a major challenge, especially for small companies. The implementation of innovative ideas is often accompanied by the need for suitable machines with which the new manufacturing steps can be realized. The acquisition of such special equipment for experimental purposes represents a financial risk. An addition to the process capacities of Fraunhofer ISIT's Assembly and Joining Technology (AVT) helps to mitigate this risk.

Ionic impurities can lead to electrochemical migration (ECM) in the presence of potential differences under the influence of moisture and thus ultimately to failure of the electronics. In particular, the application of higher voltages in the field of power electronics and increasingly also in the automotive sector places high demands on system quality and reliability. In order to provide another building block for reliability assessment, surface resistance measurements are performed at ISIT using a SIR PCB with 10 standard combs. Up to 80 channels can be measured in parallel as standard.

The proportion of women in research and development has increased sharply in recent years, especially at universities. In 2021, according to Statista, a share of over 50% of female research staff has been recorded in these institutions. What has already started at universities and colleges will hopefully soon reach other areas of the economy. Science still has a stronger attraction for men than for women. On the occasion of the »International Day of Women & Girls in Science«, Maria Claus, Deputy Head of Fab and team leader of sections lithography, bonding and metrology at Fraunhofer ISIT, answered our questions and encourages young girls and women who are interested in a career in science and research.

Batteries have an immense importance for our daily life and the number of possible and more and more specific applications is constantly growing. Lithium-ion batteries (LIB) are the most advanced battery systems today. They are used for a very wide range of applications, from cell phones to electric cars.

Sounds a little like something from days gone by, but in the age of artificial intelligence, autonomous driving and quantum computers, it is still the first step when it comes to realizing an initial idea, writing a piece of paper and something when building or implementing an application-oriented demonstrator. This sketch is the basis for the further design process. Based on this idea, a 3D model is used to give the whole thing precise contours, fix the dimensions, introduce further innovative aspects and, last but not least, to make the basic structure visualizable and imaginable for the development team. Already at this stage, errors can be detected early on and naturally avoided.

While chlorine and ultraviolet light are the standard means of disinfecting water, ozone is equally effective in killing germs. To date, ozone has only been used as an oxidation agent for treating water in large plants. Now, however, a project consortium from Schleswig-Holstein is developing a miniaturized ozone generator for use in smaller applications such as water dispensers or small domestic appliances. The Fraunhofer Institute for Silicon Technology ISIT has provided the sensor chip and electrode substrates for the electrolysis cell.