US 12,228,808 B2
Semiconductor-based optical modulator
Hamed Pishvaibazargani, Stittsville (CA); and Masaki Kato, Palo Alto, CA (US)
Assigned to Marvell Asia Pte Ltd, Singapore (SG)
Filed by Marvell Asia Pte Ltd, Singapore (SG)
Filed on Apr. 29, 2022, as Appl. No. 17/733,587.
Claims priority of provisional application 63/182,436, filed on Apr. 30, 2021.
Prior Publication US 2022/0350179 A1, Nov. 3, 2022
Int. Cl. G02F 1/015 (2006.01); G02F 1/025 (2006.01); G02F 1/21 (2006.01)
CPC G02F 1/025 (2013.01) [G02F 1/0151 (2021.01); G02F 1/212 (2021.01)] 25 Claims
OG exemplary drawing
 
1. An optical modulator, including:
a semiconductor substrate;
an optical waveguide portion disposed on the semiconductor substrate, the optical waveguide portion configured to provide an optical path for light that is to be modulated;
a first P-N junction disposed on the semiconductor substrate along the optical path, the first P-N junction defining a border between an N-doped portion disposed on the semiconductor substrate and a P-doped portion disposed on the semiconductor substrate, the P-doped portion having a uniform doping level; and
a second P-N junction disposed on a portion of the semiconductor substrate alongside the optical path and spaced apart from the first P-N junction by the P-doped portion, the P-doped portion extending from the first P-N junction to the second P-N junction; and
a reference point disposed on the semiconductor substrate alongside the first P-N junction, the reference point electrically coupled in series with the first P-N junction and the second P-N junction, the reference point configured to be held at, via electrical coupling, a DC reference potential.