Superconducting Qubit Fabrication in India: Scaling the Quantum Leap

The problems being solved

The heart of a superconducting qubit is the Josephson junction—a delicate sandwich of superconducting layers separated by a thin insulating barrier. Fabricating these junctions with atomic-level precision and uniformity across large arrays is one of the hardest manufacturing challenges in quantum computing. Even minor variations in junction area or barrier thickness can degrade qubit coherence and gate fidelity.

Beyond the junction itself, the dominant two-dimensional layout of qubit chips imposes fundamental limits. As qubit counts rise, planar designs suffer from crosstalk, wiring congestion, and reduced connectivity. Innovators are therefore rethinking geometry entirely, moving qubit patterns into the third dimension to unlock denser, more connected architectures.

Integrating multiple chips vertically introduces its own set of hurdles. Bonding superconducting layers without introducing defects, maintaining ultra-clean interfaces, and preserving the fragile quantum states across bonded interfaces are all open problems that must be solved for 3D-stacked quantum processors to become practical.

• Precision fabrication of Josephson junctions with sub-micron uniformity
• Overcoming crosstalk and connectivity limits of 2D qubit layouts
• Maintaining coherence and clean interfaces in vertically bonded 3D stacks

How the field is solving it

One inventive route is the vertical Josephson junction, formed not by the usual planar deposition but by etching a perpendicular trench into the substrate and then evaporating the superconductor at an angle—without rotating the wafer. This creates the junction on a vertical sidewall, decoupling junction area from the chip’s lateral footprint and enabling denser qubit packing.

Another approach arranges superconducting patterns on multiple differently oriented surfaces of an insulating base. By placing qubit elements on faces that are not all in the same plane, the design naturally extends into three dimensions, increasing connectivity and reducing the wiring overhead that plagues large 2D chips.

For true 3D integration, thermo-compression bonding with tantalum and gold layers is being explored. This technique fuses separate chips under heat and pressure, creating robust superconducting interconnects. Tantalum, prized for its low microwave loss, and gold, for reliable bonding, together aim to preserve the quantum coherence that is so easily lost at imperfect interfaces.

• Vertical Josephson junctions via angled evaporation into perpendicular trenches
• Superconducting patterns on multiple oriented surfaces for native 3D qubits
• Thermo-compression bonding with tantalum-gold stacks for vertical integration

Where the market is heading

The global superconducting quantum chip market was valued at roughly USD 600 million in 2025 and is projected to grow at a double-digit annual rate through 2035, according to Future Market Insights. India’s broader quantum computing market, estimated at about USD 1 billion in 2024, is expected to expand at a compound annual growth rate of around 27% to reach roughly USD 7 billion by 2032, as noted in a LinkedIn analysis of the country’s quantum landscape.

India’s National Quantum Mission has allocated approximately USD 750 million over eight years, signaling a strong government push to build domestic capabilities in quantum hardware. Local fabrication of superconducting qubit chips is anticipated to begin within the next few years, with roadmaps targeting systems of increasing qubit count and, eventually, error-corrected logical qubits.

Across the industry, the focus is shifting from proof-of-concept qubits to engineering reliable, scalable processors. Improving coherence times and gate fidelities in transmon-style qubits, tackling material defects like two-level system noise, and integrating quantum fabrication with classical semiconductor processes are all active fronts. Supply chain resilience for critical components is also becoming a strategic priority.

• Global superconducting chip market: ~USD 600M in 2025, growing at 17%+ CAGR (Future Market Insights)
• India’s quantum market: ~USD 1B in 2024, projected ~USD 7B by 2032 at ~27% CAGR
• National Quantum Mission: ~USD 750M over 8 years to boost indigenous quantum tech
• Engineering focus: coherence, material purity, CMOS-compatible fabrication, supply chain

The white space

While 3D integration promises to break the scalability barrier, the community has yet to fully solve how to maintain qubit coherence across bonded interfaces. Every additional processing step—etching, bonding, annealing—introduces potential sources of decoherence. Developing fabrication protocols that keep defect densities vanishingly low in three-dimensional stacks is a rich area for innovation.

Another open frontier is the scalable production of uniform Josephson junctions across large qubit arrays. As processors move from tens to hundreds and thousands of qubits, the tolerable variation in junction parameters shrinks dramatically. Techniques that can reliably reproduce identical junctions wafer after wafer, without sacrificing yield, represent a significant opportunity for new fabrication methods and in-line metrology.

These gaps are not signs of stagnation; they are precisely the kind of deep-tech challenges that attract inventive minds. Solving them could unlock the next generation of error-corrected quantum processors, and India’s growing quantum ecosystem is well-positioned to contribute novel solutions in materials, process engineering, and 3D integration.

• Maintaining qubit coherence in 3D-stacked architectures
• Scalable, uniform Josephson junction fabrication across large arrays
• Ultra-clean processing and metrology for high-yield quantum chip manufacturing

Explore the innovators

The specific inventors, patents, and companies driving superconducting qubit fabrication forward in India can be explored in depth on Deeptech Navigator. There you’ll find the detailed problem statements, technical approaches, and the people behind them—all mapped to the real patent landscape. It’s an invitation to see exactly where the breakthroughs are being made and who is making them.

In our data

Sources

• How to make a superconducting qubit ↗
• A quantum engineer's guide to superconducting qubits ↗
• Superconducting qubits: Delicate powerhouses ↗
• The Supply Chain Chokepoints in Quantum ↗
• The Foundry's Hidden Supply Chain: Who Really Wins If ... ↗
• Material Challenges for Superconducting Quantum Chips ↗
• Quantum Computing Market Size, Share & Trends ↗
• Superconducting Quantum Chip Market | Global Market Analysis Report ↗