Fig. 1. Multi-thousand channel PtNRGrids ECoG arrays.

(A) Scalable and large-area fabrication of electrode arrays on 18 × 18 cm² glass substrates. Microscale features of PtNRs contacts, metal leads, and perfusion holes shown by (B) optical (top) and electron microscope images (bottom). (C) A 1024 channel electrode bonded on the extender PCB that is compatible with CPU LGA sockets. Reconfigurable electrode designs depending on the target placement on the human brain with a sensing area of (C) 32 × 32 mm² (1024 channel), (D) 8 × 8 cm² (2048 channel), and (E) 3 × 13 mm² (1024 channel). (F) Spatial mapping and (G) histogram of the impedance magnitude at 1 kHz for the 1024 and 2048 channel electrode. 1024 and 2048 channel electrodes had 1 kHz impedance magnitude of 11 ± 2 kΩ and 8 ± 4 kΩ with a yield up to 99.4 and 95.2%, respectively.