Academic Visit at DST - IIEST Solar PV Hub, Shibpur

• 27 March 2025

Intro :

We had an incredible industrial visit to the DST - IIEST Solar PV Hub at IIEST Shibpur, where we explored cutting-edge research in solar energy and renewable technologies. The visit featured insightful demonstrations by renowned professors, including our beloved Dr. Sukanta Bose, Prof. Sumita Mukhopadhyaya, and Prof. Santanu Maity Sir (HOD, SAMGESS),Biplob Saha , Rittik Majumdar , Tushar Sir who shared their expertise on advanced materials, green energy, and sensor systems.

The day began with an awesome lecture by Prof. Sumita Mukhopadhyaya, who provided a comprehensive overview of the day's lab tour and the exciting research being conducted at the institute.

Thin Film Silicon Deposition Laboratory :

Then, after lunch, we all visited the Clean Room Lab and the Thin Film Silicon Deposition Lab, where we explored the Solar Cell (Thin Film) Fabrication Facility, featuring:

1. Plasma Enhanced CVD CT150: The Plasma-Enhanced Chemical Vapor Deposition (PECVD) CT150 system is used for depositing thin films by converting precursor gases into a solid-state coating on a substrate. This process involves chemical reactions that occur after plasma generation using radio frequency (RF) or direct current (DC) discharge between two electrodes. The plasma is created using either alternating current (AC) or direct current (DC), which energizes the reacting gases in the chamber, enabling film deposition at lower temperatures compared to conventional CVD methods. It is widely employed in industries such as solar cell manufacturing, where it is used for depositing amorphous silicon (a-Si:H) layers, as well as in microelectronics, MEMS devices, optical coatings, and protective thin films.
2. PlasmaEnhanced CVD CT100: This type of PECVD is used to make a solar cell with crystalline silicon.

The entire process is controlled by a PECVD Cluster Tool, which operates using PLC SCADA programming, ensuring precise automation and monitoring of fabrication.

Material Deposition Fabrication Laboratory ;

Next, we visited the Material Deposition Fabrication Laboratory, which houses:

1. RF Sputtering Unit: DC sputtering utilizes a DC gaseous discharge. Ions strike the target (the cathode of the discharge), which is the deposition source. The substrate and the vacuum chamber walls may be the anode. the power supply is simply a high-voltage DC source. RF-sputtering is a suitable technique to fabricate optical planar waveguides and photonic microcavities operating in the visible and NIR regions. Sputtering techniques are widely used in industrial process because high quality films can be obtained at low temperature substrates. We have also demonstrated as the rf sputtering is a suitable technique for fabrication of dielectric microcavities and it is a cheap and versatile technique to deposit alternating layers of different materials with controlled refractive index and thickness. With these advantages, as well as the possibility to incorporating QCM, RF-sputtering process is a extremely appropriate candidate to fabricate high quality and homogeneous 1-D photonic.

2. Reactive Ion Etching Unit: Reactive-ion etching(RIE) is an etching technology used in microfabrication. RIE is a type of dry etching which has different characteristics than wet etching. RIE uses chemically reactive plasma to remove material deposited on wafers. The plasma is generated under low pressure(vacuum) by an electromagnetic field. High-energy ions from the plasma attack the wafer surface and react with it .

3. Thermal and E-Beam Evaporation Unit: Electron-beam physical vapor deposition, or EBPVD, is a form of physical vapor deposition in which a target anode is bombarded with an electron beam given off by a charged tungsten filament under high vacuum. The electron beam causes atoms from the target to transform into the gaseous phase. These atoms then precipitate into solid form, coating everything in the vacuum chamber (within line of sight) with a thin layer of the anode.

Diffusion Laboratory :

Following this, we explored the Diffusion Laboratory, where we learned about:

1. P/P+ & N/N+ Thermal Oxidation-Diffusion Furnace : A P/P+ & N/N+ Thermal Oxidation-Diffusion Furnace is used in semiconductor processing for growing silicon dioxide (SiO₂) layers and diffusing dopants into silicon wafers. The oxidation process occurs at high temperatures (800–1200°C) in an oxidizing ambient, using either dry oxidation (O₂) for high-quality thin oxides or wet oxidation (H₂O) for faster, thicker oxide growth. Since oxidation is a diffusion-controlled process, the furnace also facilitates the diffusion of dopants like boron (P-type) or phosphorus (N-type) into the wafer to modify its electrical properties. The furnace consists of a quartz tube, heating elements, a gas flow system, and precise temperature controls to ensure uniform processing. It is widely used in microfabrication for forming gate oxides, isolation layers, and doping junctions in semiconductor devices.

Lithography Laboratory in Clean Room :

Finally, we visited the Lithography Laboratory in Clean Room, which includes:

1. Surface Conformal Imprint Lithography Laboratory: The surface conformal imprint lithography (SCIL) system allows for sub-100nm imprinting of features. Using a hard master, a soft replica stamp is made using PDMS and flexible glass sheet. The result is a flexible stamp that readily conforms to existing substrate topography when imprinting atop a UV curable nano-imprint resist. This machine cost approx 2.5 Crore.

Various types of machines :

We also visited a wonderful lab to learn about various types of machines, which are newly established facilities under the DST Project.

• Single Side Etcher: This device enables precise etching of materials on a single side of a substrate, commonly used in microfabrication and semiconductor industries to create intricate patterns and structures.​

• Green LASER: Emitting light at approximately 532 nm, green lasers are utilized in applications such as spectroscopy, holography, and biomedical imaging due to their high visibility and coherence.​

• Ellipsometer: An optical instrument that measures the change in polarization as light reflects or transmits through a sample, providing critical information about thin film thickness and optical properties.​

• Weather Chamber: A controlled environment chamber that simulates various climatic conditions, allowing researchers to test the durability and performance of materials and products under different temperature and humidity levels.​

• UV Chamber: This equipment exposes materials to ultraviolet light to study their resistance to UV radiation, aiding in the assessment of material longevity and the development of UV-resistant products.​

• Solar Simulator: Designed to mimic natural sunlight, solar simulators are used to test solar cells, photovoltaic panels, and other materials under standardized light conditions, ensuring consistent performance evaluations.​

• EL Tester: Electroluminescence testers detect defects in photovoltaic modules by capturing emitted light when an electrical current passes through, assisting in quality control and performance assessment of solar panels.​

• IR Heating Furnace: Utilizing infrared radiation, this furnace provides uniform and efficient heating for processes such as annealing, sintering, and drying, commonly employed in materials science and engineering applications.​

  These instruments collectively enhance the research capabilities at IIEST Shibpur, supporting advancements in engineering and technology.

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Fig : Ellipsometer

Fig : Weather chamber

Fig : EL Tester

Fig : Solar Simulator

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We also knew very interesting informations from the faculties of IIEST, Shibpur as follows

• RABI KUTIR - BIPV SOLAR COTTAGE Lab for solar PV systems: It is a Green Building inaugurated in the year of January’2011. The roof of the building is totally made of solar PV modules. The bricks are air insulated to maintain the inside temperature of the building constant throughout the year. It is an energy efficient building which also maintain the aesthetic view of the surroundings.

• Three renewable energy plants:

  • Solar Panel: There are various applications of solar cells. One innovative example is a smart toilet designed by professors and students of IIEST, which integrates a solar panel, a microcontroller, and MATLAB program simulation.
  • Wind Mill: There is also a well-established wind energy plant for power generation. However, due to time constraints, the professors decided not to visit it.
  • Biogas Plant: A great initiative has been undertaken to reduce food waste. The leftover food is first stored in a mixing machine and then transferred to the biogas production chamber, which has two partitions. These partitions help separate heavy materials, light materials, and oil. The resulting biogas, which contains methane and other gases. Tushar Sir demonstrated how power is generated from this process. He also learned about the full operation of the plant and, upon starting the generator, observed the voltage level increasing to 300–350V, turning the lights on. Additionally, Professor Santanu Maity discussed future plans for the biogas plant, including the production of vermicompost for sale, which could serve as a significant source of income.

• High-Value (Above ₹1 Crore) Projects at IIEST Shibpur:

  • DST Solar PV Hub at IIEST Shibpur – ₹26 Cr.
  • Advanced Research on Thin-Film Silicon Solar Cells and PV Systems – ₹14.761 Cr.
  • Going Remote – Solar Energy for Lighting and Hygienic Sanitation with Smart Exhaust Systems for Rural Applications (DST-CERI) – ₹2 Cr.
  • High-Efficiency Triple Tandem and Hetero-Junction Silicon-Based Solar Cell – ₹10 Cr.
  • Several other ongoing/completed projects at IIEST Shibpur.

• Their mission is to provide the Solar PV Hub and the associated researches a global identity and the vision is to promote the incubation of next-generation green technologies through partnerships with academic institutions and industries and transfer the developed skills and technology to the society.

• Their major research areas are c-Si solar cells, Thin film solar cells, Super capacitors and energy storage devices, Hetero junction solar cells, Photodetectors, PV modules, EDS (Electrodynamic Dust Shield), Biosensors and Gas sensors etc.

• IIEST Shibpur has also planted a Solar Tree for the ECO Park. Solar trees offer a unique and visually striking way to harness solar energy. They generate clean, sustainable energy, reducing our reliance on fossil fuels and decreasing greenhouse gas emissions. By incorporating solar trees, we move towards a greener and more environmentally responsible future.

• IIEST Shibpur has introduced a Solar Boat for the ECO Park, promoting clean energy and sustainability. It reduces carbon emissions, noise pollution, and reliance on fossil fuels while supporting eco-tourism and cleaner waterways. Additionally, solar boats create jobs, enhance public transport, empower fisherfolk, and serve as mobile power plants for remote areas.

Special thanks :

Special thanks to the Students’ Chapter of IEI ECE, Academy of Technology, for sponsoring this visit, as their support made this experience possible. We are also deeply grateful to Prof. Sukanta Bose for her invaluable guidance, which made this academic visit truly special. Our five-hour visit to IIEST Shibpur was highly fruitful, providing us with valuable insights into fabrication techniques, solar cells, renewable energy, and various other advanced topics. Adding to the experience, the delicious food treat from the Students’ Chapter of ECE was a delightful gesture that made the visit even more enjoyable. This experience has undoubtedly sparked a deeper interest among students in these fields, encouraging further exploration and learning.

Written by

Soumojit Shome & Srijit Mukherjee