Nanometer structures are punched into brittle silicon that is subjected to high pressure metered at tolerances of less than 1 micrometer while the microchips are contacted and packaged using a range of elaborate processes. Machine manufacturers such as Smart Equipment Technology (SET) SAS continue to push the envelope of what is technically possible in semiconductor production. The company’s Die Bonder FC 300 carries out a number of the production steps. A NYCe 4000 motion controller from Rexroth regulates the operational processes through a SERCOS III network.
Two years ago, the 100-nanometer structure mark was the benchmark. Today, a few chip manufacturers are already producing modules with structures that measure fewer than 20 nanometers. Smart Equipment Technology’s high-precision bonding and nanoimprint lithography machine – the FC300 –adapts to a number of processes for producing microchips and optoelectric components with nanostructures.
More plants are converting over to the new 300 mm silicon wafers to lower production costs, since considerably more chips will fit on the larger substrates. In these applications, such as nanoimprint lithography, the FC300 applies different front-end and back-end processes that require high forces and ultrahigh precision. Unlike with photolithography, nanoimprint lithography involves a die that mechanically stamps the structures.
The vertical axis of the SET machine produces up to 4,000 N of pressure, which is applied to the brittle silicon wafer in micro-metered movements. The controller must receive and evaluate many different sensor signals and translate them into motion commands in real time. The scalable multi-axis control system combines the control and drive hardware in one housing. Its footprint is smaller than an industrial PC. Application-oriented programming controls motor speed and precision; up to ten motors can be controlled. With up to 120 digital and analog inputs/outputs, it is possible to integrate a large number of measuring units for complex process steps. The NYCe 4000 in the FC300 regulates linear, piezo, stepper, servo synchronous, and torque motors. It evaluates the signals of all encoder types, the initial SinCos control signals of high precision position measuring systems, and the EnDat 2.1, EnDat 2.2, and Hiperface logs to achieve the required contacting accuracy of 0.5 micrometers.
End-to-end SERCOS III communication provides the bandwidth required for this through a Fast Ethernet infrastructure. SERCOS III also enables short cycle times and high reliability.
The FC 300 likewise incorporates process steps for contacting and packaging the integrated circuits (bonding), where the motion controller regulates complex motion sequences and process evaluations at the touch of a button.
High forces similar to those of nanoimprint lithography are applied at the vertical axis when multiple chips are bonded to form three-dimensional, integrated circuits. Here, too, the motion controller precisely meters the force applied. The operator can also create a vacuum and introduce industrial gases into the process chamber in addition to carrying out these processes under normal atmospheric conditions. Large components (to 100 mm x 100 mm) can be bonded as well.
The automation system accommodates the large variance between processes entirely through software. This, in turn, makes it possible to introduce smaller structures for even higher-performance microelectronics.
Bosch Rexroth Corporation