Electronic devices have become an integral part of our daily lives, and our interaction with them is no longer limited to industry and offices. A deeper look into the devices we have come to take for granted reveals a world of integrated circuits – including one of their primary components: the silicon wafer. Semiconductor coatings applied to the silicon wafer provide protection as well as various functional benefits.
Semiconductor fabrication isn't complete until the silicon wafer has undergone the process of physical vapor deposition (PVD). PVD is a thin film deposition technique, where electrically conductive materials such as a pure metal or alloy are coated with vaporised solid metal in a high vacuum environment. Thin film deposition techniques are also used for electronics sent to space to orbit the earth for various purposes. With such wide-ranging applications, it is vital that electronic devices are rugged, while at the same time ensuring high performance and quality.
Emerging as a worldwide leader in high vacuum technology, the HHV group is fully focused on the design and development of vacuum equipment, solar equipment, vacuum hardware, thin film and optical products and high-tech solar modules. The group is also a prime contractor for large custom projects based on vacuum technology. HHV was established in 1965 as a specialised enterprise aimed at developing Indian self-reliance in high vacuum technology for the scientific and industrial communities. Today, it is ranked among the global leaders in vacuum hardware and has an international market for its photovoltaic energy products.
Thin film deposition – the process of applying a thin coating to a surface from a vaporous or dissolved state – is on its way to becoming one of the building blocks of nanotechnology. The BT150 and BT300-series from HHV provide laboratories and test setups with a compact tabletop machine for thin film coating of products. This has helped Indian scientists study the effects of thin film coating on products and conduct thorough testing before deploying them in the field.
The product to be coated has to be placed in a closed environment and is loaded into the machine manually. As these setups are designed for use in laboratories, there is no need to automate the loading process. Inside the chamber, a rotating platform controlled by a stepper motor ensures that the product is coated evenly.
The thin film coating process requires a vacuum environment, which is generated in the closed chamber by a vacuum pump. Only one product can be coated per machine cycle, which is ideally around 10-15 minutes.
Once the product has been loaded and the chamber is closed, the machine can perform the thin film coating process in automatic or manual mode. The process begins with 4 steps to establish the necessary environment – vacuuming, preprocessing, processing and venting. First, a vacuum pump removes air and fine dust to generate a vacuum inside the chamber, which takes around five to ten minutes.
The next step, preprocessing, involves adding a gas to the vacuum chamber, followed by a high-voltage charge that further removes impurities and oxides. The user is able to define the thickness and the number of layers needed for coating. Usually the thickness is measured in angstroms and the BT150/BT300 machines are capable of coating up to six layers using different materials, taking around three to five minutes depending on the thickness and number of layers. A frequency-based input is used to measure the coating thickness and provide feedback to the control system so that the process stops when the desired thickness is achieved.
After this, the chamber needs to be vented before it can be opened to remove the coated product. The venting process slowly removes the vacuum from the chamber over the course of about five minutes. The BT line fits perfectly in a laboratory, which makes it the ideal tool for a lot of routine deposition processes and for small-scale teaching laboratories.
Achieving high accuracy is a primary goal for any organisation. The quality standards needed for electronics make accurate coating thickness an essential requirement for thin film coating. HHV has worked closely with world renowned scientists to develop challenging and advanced thin film deposition systems.
This unique equipment has successfully demonstrated its functional performance, product quality and repeatability. "The coating thickness and accuracy achieved by our BT300/BT150 machines is measured in angstroms," says Subramanya Shastry, General Manager of HHV. "We, at HHV, are proud of the fact that no competitor product comes close to matching our best-in-class accuracy: an amazing 0.1 angstroms."
General Manager, HHV
“With B&R, we need considerably less time to commission our machines. Our machines have become both smarter and more compact. Our close cooperation has built a strong foundation of trust making B&R our preferred automation vendor.”
The challenges of building a compact tabletop machine start with the mechanical design and carry over into the control system as well. "Our customers are always demanding new features and keep a close eye on the market for better, more competitive products," notes Gadigeppa Battikoppada, Assistant Manager - Design at HHV. "We focus on providing them with cost-effective machines that deliver superior performance."
B&R has long been known for its compact control and I/O systems. HHV instantly found B&R to be an ideal fit for the needs of the BT150/BT300 machines, offering unmatched features. B&R's Power Panel C-Series provides crisp, high-resolution HMI with a built-in controller. The unique 3-part design of the hot-pluggable remote I/O modules in B&R's X20 system make installation and maintenance remarkably simple. The system's compact dimensions – encapsulating all of the machine's I/O needs in a slender 12.5 centimeters – help HHV save a tremendous amount of space.
"With the number of machine variants growing exponentially due to the varied demands of our customers, managing software and machine programs becomes an important challenge," explains Battikoppada. "As a universal development environment for all B&R products, Automation Studio has made managing programs for machine variants easier than ever. It enables us to maintain a single project with separate configurations for each variant."
mapp Technology framework, available as a plug-in for Automation Studio, further reduces programming complexity by providing ready-made components that allow HHV to program less and configure more. This has drastically reduced development times and improved machine diagnostics.
"With B&R, we need considerably less time to commission our machines. Our machines have become both smarter and more compact," says Shastry. Recipes can be called up at any time for coating different products with different needs. New recipes can be added and existing ones can be edited on the fly and used for future products.
"We are extremely pleased to have B&R as our automation partner and plan to take the partnership to new levels with numerous research projects already in pipeline," concludes Sashtry. "Our close cooperation has built a strong foundation of trust. We can pass on new requirements from our customers to B&R with confidence. The swift responses, focused problem-solving and technical knowledge of the entire B&R team – together with their world class, innovative products – has made B&R our preferred automation vendor."
Assistant Manager - Design , HHV
“We provide accuracy down to an amazing 0.1 angstroms. Our customers are always demanding new features and we provide them with cost-effective machines that deliver superior performance.”
As a universal development environment for all B&R products, Automation Studio make managing programs for machine variants easier than ever. It enables HHV to maintain a single project with separate configurations for each variant.