BAE requalifies RH45 rad-hard ASIC platform

BAE Systems has received $16 million in US Defense Production Act Title III funding to demonstrate and qualify its RH45 radiation-hardened semiconductor platform, restoring a route for custom ASIC development in space and other high-radiation environments.

RH45 is based on GlobalFoundries’ 45nm silicon-on-insulator process at its Malta, New York manufacturing site. BAE Systems provides qualified design building blocks around the process so customers can develop application-specific devices using established semiconductor design tools rather than starting with an unqualified commercial technology.

Radiation-hardened ASIC development puts different constraints on a design than mainstream commercial silicon. Performance, power and die area remain important, but spacecraft electronics also have to tolerate radiation effects capable of corrupting stored data, altering logic states or damaging transistors over time.

Qualification therefore extends well beyond proving that a chip works under ordinary laboratory conditions. Device structures, standard cells, memory elements and design rules have to be characterised against the relevant radiation mechanisms, while manufacturing and test processes must remain controlled throughout programme lifetimes that can span many years.

BAE Systems says RH45 has supported customer ASIC programmes for more than a decade. The new funding is intended to demonstrate and requalify the technology on GlobalFoundries’ 45nm SOI flow and restore the storefront through which customers access the hardened design infrastructure.

Silicon-on-insulator is useful in this environment because active device regions are electrically isolated from the bulk substrate. SOI does not make a circuit intrinsically radiation hardened, but it provides a process foundation on which hardened cell libraries, layout methods and verification techniques can be developed.

The use of a 45nm node also reflects the different economics of space electronics. Commercial processors have moved far beyond 45nm, but mission hardware values characterised behaviour, long-term availability and manufacturing stability alongside density. A spacecraft may be designed several years before launch and remain in operation for a decade or longer afterwards.

Custom ASICs give system architects another option between fixed catalogue components and full general-purpose processors. Functions such as interface control, encryption, signal processing or acceleration can be consolidated into a device designed around a particular payload or platform.

That consolidation can reduce board area, component count and power while improving deterministic performance, although the non-recurring engineering cost means the approach is most attractive where mission requirements justify the investment.

The manufacturing route also carries a supply-chain dimension. GlobalFoundries will fabricate the technology in New York, while BAE Systems’ Space Systems operation in Manassas, Virginia performs RH45 design and support work.

BAE identifies the Manassas site as a US Department of Defense Category 1A Microelectronics Trusted Source covering design, aggregation, brokering, packaging and assembly, and test services. For national-security programmes, provenance and control of those stages can be as important as the electrical characteristics of the finished device.

The RH45 technology is also being integrated into BAE Systems’ Endura single-board computer programme. Endura is intended to combine processing cores, hardware-accelerated I/O and security functions in a higher-level computing assembly that spacecraft manufacturers can integrate as a subsystem rather than developing every electronic function at board level.

That connection between ASIC infrastructure and board-level computing is significant. A qualified semiconductor process provides the building blocks, but system designers ultimately need processors, memory, interfaces, software and mechanical packaging that can survive the complete mission environment.

The $16 million programme is therefore less a conventional product launch than an investment in the design and manufacturing chain behind future devices. Requalifying RH45 gives spacecraft developers access to a US-manufactured 45nm platform for custom radiation-hardened electronics at a time when payload computing requirements are increasing faster than the environments in which those circuits must survive are becoming any more forgiving.