US 12,302,649 B2
Inversion layer avalanche photodiode with vertical electric field
Gianlorenzo Masini, Carlsbad, CA (US)
Assigned to Cisco Technology, Inc., San Jose, CA (US)
Filed by Cisco Technology, Inc., San Jose, CA (US)
Filed on Nov. 11, 2022, as Appl. No. 18/054,871.
Prior Publication US 2024/0162366 A1, May 16, 2024
Int. Cl. H10F 30/225 (2025.01); H10F 71/00 (2025.01); H10F 77/122 (2025.01); H10F 77/14 (2025.01); H10F 77/40 (2025.01)
CPC H10F 30/2255 (2025.01) [H10F 71/121 (2025.01); H10F 77/122 (2025.01); H10F 77/148 (2025.01); H10F 77/413 (2025.01)] 20 Claims
OG exemplary drawing
 
1. An avalanche photodiode (APD), comprising:
a buried oxide layer;
a silicon layer disposed on the buried oxide layer, the silicon layer comprising:
a lightly doped region contacting the buried oxide layer, the lightly doped region forming an inversion layer at an interface between the buried oxide layer and the silicon layer, and
a P doped region above the lightly doped region; and
a germanium absorption region above the P doped region, wherein, during operation, the APD includes a vertical electrical field in the germanium absorption region, the P doped region, the lightly doped region, and the inversion layer.