Flexible solutions for optical quality control
Mr. Falk, what are the main applications of MueTec systems?
Our systems are designed for non-contact, non-destructive measurements of topological structures, as well as defect inspection. For example, a large group of problems is associated with the control of the critical dimensions of topological elements. The critical dimension value is calculated by analyzing the halftone image obtained with the CCD camera. The analysis is performed automatically by the MueTec Tools software, taking into account the CCD noise and distortions caused by optical diffraction. For sub micrometer measurements, ultraviolet illumination (365 nm) can be used.
One of the popular options is to control the thickness of transparent films on a non-transparent substrate. The measurement method is based on the spectral analysis of laser beam reflected from the interfaces of the layers. It is possible to measure the thickness of single-, double- and triple-layer transparent films.
We also have extensive experience in creating software and hardware solutions for defect inspection in semiconductor structures in automatic or semi-automatic modes. Systems of this type are based on comparing the image obtained when scanning the surface of the wafer with the reference image. Our software uses special algorithms for object recognition and analysis, as well as for filtering scanning errors.
For defect inspection and measurements, it is possible to use devices with IR optics and InGaAs cameras that provide IR imaging with high resolution and good contrast. Such equipment is used, first of all, in the production of MEMS for inspection of wafer bonding and sealing, detection of defects and impurities, as well as in sub micrometer measurements.
It is very important that our instruments allow measurements not only on semiconductor wafers, but also on photomasks. Such measurements and defect inspection can be performed in both reflected and transmitted light.
In which devices are these measurement methods implemented?
The MT2010, MT3000 and MT8000 systems are offered for the control of critical dimension, overlay and film thickness, as well as for the defect inspection. The first two are designed for 100 mm/200 mm wafers, the third – for 200 mm/300 mm wafers. MT1000 is created specifically for automatic inspection of macro-defects on 100% of the wafer area. The throughput of this model is up to 200 wafers per hour. IRIS2100 and IRIS8200 systems are designed for IR metrology. In addition to these standard models, we have extensive experience in creating customized measuring systems and tools.
What are the main advantages of MueTec solutions?
First, the great advantage is the high flexibility of our systems, which allows them to be used in the design and manufacture of various types of devices, including power electronics and MEMS. Secondly, as I already mentioned, we offer solutions that are optimized for the needs of customers. Almost every project includes at least one or two options for the specific requirements of a particular enterprise or scientific center. Third, we are a German company committed to high quality traditions. Our systems are based on the tools of the world's leaders in the field of optical measurements – Leica, Carl Zeiss and KLA-Tencor, which are supplemented by our own developments in the field of hardware and software.
How do the requirements for measuring equipment change?
There are two trends, which are partly contradictory, but should be taken into account equally in the development of modern measuring systems. On the one hand, customers want the tool to be as versatile as possible and can be used for a wide range of applications, on the other hand, it should be extremely easy in use. Somewhere between these limiting conditions lies the way in which the development of modern technology is going on, and we are striving for our solutions to correspond to as much as possible to both trends.
Interview: Dmitry Gudilin