In high-tech products, there is an increasing demand to integrate glass lenses into complex micro systems. Especially in the lighting industry LEDs and laser diodes used for automotive applications require encapsulated micro lenses. To enable low-cost production, manufacturing of micro lenses on wafer level base using a replication technology is a key technology. This requires accurate forming of thousands of lenses with a diameter of 1-2 mm on a 200 mm wafer compliant with mass production. The article will discuss the technical aspects of a lens manufacturing replication process and the challenges, which need to be solved: choice of an appropriate master for replication, thermally robust interlayer coating, choice of replica glass, bonding and separation procedure. A promising approach for the master substrate material is based on a lens structured high-quality glass wafer with high melting point covered by a coating layer of amorphous silicon or germanium. This layer serves as an interlayer for the glass bonding process. Low pressure chemical vapor deposition and plasma enhanced chemical vapor deposition processes allow a deposition of layer coatings with different hydrogen and doping content influencing their chemical and physical behavior. A time reduced molding process using a float glass enables the formation of high quality lenses while preserving the recyclability of the mother substrate. The challenge is the separation of the replica from the master mold. An overview of chemical methods based on optimized etching of coating layer through small channels will be given and the impact of glass etching on surface roughness is discussed

Currently, security issues for semiconductor chips are counterfeiting and night shift problems. These factors might lead to insecure supply chains in the automotive industry. This can be avoided by using coating Physical Unclonable Functions (PUFs). The coating can be applied to every semiconductor chip in order to create a unique fingerprint. In this work, a 2-bit key per capacitor for Physical Unclonable Functions is presented for the first time. For this reason, 49 chips on a wafer with 195 metal oxide semiconductor (MOS) capacitors were fabricated. A large and random fluctuation of the capacitances was achieved by using a self-developed layer, which consisted of aluminum particles and spin-on glass. Due to the random variation in size and change in distribution of the particles, the fluctuation of capacitance varied from chip to chip and from wafer to wafer. The achieved large range in capacitance was used to create a 390-bit string out of 195 capacitors. Although the length of the bit string was doubled, the area of the structure remained constant. This led to a more secure PUF with a low error rate of 0.21 % and an inter-chip Hamming distance (HDinter) of 49 %.

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