APECS – European pilot line for advanced packaging and heterogeneous integration
Radio Frequency (RF) Chiplet
Target
Development and validation of complex, integrated RF systems up to 325 GHz through four coordinated sub-demonstrators covering mobile communication, wireless links, and radar applications. Focus lies on heterogeneous integration of III–V, SiGe/BiCMOS and FDSOI CMOS technologies and the validation of the APECS design enablement (PDKs, ADKs, tools), including testing and pilot-line verification.
Innovation
Heterogeneous integration of RF chiplets across multiple semiconductor platforms using interposers, flex substrates, and fan-out wafer level packaging (FOWLP). Enables compact, scalable mm-wave and sub-THz modules with improved efficiency, bandwidth, and system-level performance for radar, sensing and communication applications.
Approach
Four complementary sub-demonstrators:
1) InP-on-BiCMOS 6G D-band transceiver (110–170 GHz)
- Microbump integration
- Four-channel scalable architecture
- Improved output power and efficiency
2) Sub-THz (256 GHz) BiCMOS–mHEMT radar front-end
- SiGe + InGaAs chiplets
- Flip-chip, copper pillar bonding, indium micro-bumps
- Interposer platform (fused silica / silicon)
3) 3Flex D-band radar system
- RF-glass interposer with antenna integration
- Flexible polymer substrates
- Multi-module radar architecture on non-planar surfaces
4) D-band communication module
- FO-WLP integration
- GaN + FDSOI co-integration
- Integrated cooling structures
System-Technology Co-Optimization (STCO) is applied to optimize system performance across technologies.
Progress
- Implementation of four RF sub-demonstrators
- Realization of D-band and sub-THz system concepts
- Validation of integration technologies: microbumps through silicon and glass vias (TSV, TGV), flip-chip, interposers, FO-WLP
- Development of scalable multi-module radar architectures on flexible substrates
- Establishment of STCO-based design and pilot-line validation
Partners
- Leibniz Institute FBH – InP-HBT chiplets
- Leibniz Institute IHP – BiCMOS technologies and interposers
- Fraunhofer IAF – GaN and InGaAs MMICs
- Fraunhofer ISIT – Glass interposers
- Fraunhofer IPMS – FDSOI transceiver
- Fraunhofer IZM – FOWLP integration and cooling
- Fraunofer FHR – BiCMOS D-band TX
- Fraunhofer EMFT – Radar module design (BiCMOS on Glass and Flex interposer), techn. lead
- Research Fab Microelectronics Germany (FMD) Office – coordination and support
Impact
The demonstrator validates heterogeneous integration for high-performance RF systems and demonstrates pilot-line readiness for mm-wave and sub-THz modules. It enables scalable solutions for 5G/6G communication, sensing, and radar applications, including deployment on flexible and non-planar surfaces.