Design robustness of Millimeter Wave 5G/6G Power Amplifier in Nanowire Transistor Technology
| Reference number | |
| Coordinator | C2AMPS AB - C2AmpS |
| Funding from Vinnova | SEK 389 000 |
| Project duration | November 2019 - October 2020 |
| Status | Completed |
| Venture | The strategic innovation programme Electronic Components and Systems: |
| Call | Electronic Components and Systems. Feasability Studies 2019 |
Important results from the project
A class A Power Amplifier (PA) using vertical nanowire transistors for 28 GHz, i.e. one of the frequencies that is now used in the 5G systems, has been analyzed regarding design robustness (Monte Carlo statistical simulations) before protype manufacturing. The study has shown that the circuit design is robust against process proliferation enabling manufacturing of prototypes at Lund university. To increase the yield, it would be advantageous to investigate the possibility of reducing the spread further with respect to certain parameters such as the threshold voltage.
Expected long term effects
A dominating source of distortion at millimeter wave frequencies are nonlinear (voltage dependent) parasitic capacitances in the transistor. With our process technology, these are small, which is an advantage when transmitting at high output power and at the same time obtain low distortion. In the study, efficiency, output power and EVM, have been simulated, both with a CW signal and with a modulated 64 QAM signal for 5G, with good results. The simulations, conducted with process spread, have after modifications of the design, demonstrated a sufficient robustness of the amplifier.
Approach and implementation
The implementation of the project has to the largest extent followed the plan regarding subtasks. The Corona pandemic has delayed the project though since service of process equipment has been forced to be postponed. This has been solved by combining spread data from earlier runs with data from runs during the project time frame. Important subtasks were the analysis of the contact resistance and the design of the transformers, a key component in millimeter wave design. The cooperation with Lund University has worked well.