Melissa Ziebell

40 Gbit/s low-loss silicon optical modulator based on a pipin diode

40 Gbit/s low-loss silicon optical modulators are demonstrated. The devices are based on the carrier depletion effect in a pipin diode to generate a good compromise between high efficiency, speed and low optical loss. The diode is embedded in a Mach-Zehnder interferometer, and a self-aligned fabrication process was used to obtain precise localization of the active p-doped region in the middle of the waveguide. Using a 4.7 mm (resp. 0.95 mm) long phase shifter, the modulator exhibits an extinction ratio of 6.6 dB (resp. 3.2 dB), simultaneously with an optical loss of 6 dB (resp. 4.5 dB) at the same operating point.

Ten Gbit/s ring resonator silicon modulator based on interdigitated PN junctions

10 Gbit/s silicon modulator based on carrier depletion in interdigitated PN junctions is experimentally demonstrated. The phase-shifter is integrated in a ring resonator, and high extinction ratio larger than 10 dB is obtained in both TE and TM polarizations. VπLπ of about 2.5 V × cm and optical loss lower than 1 dB are estimated. 10 Gbit/s data transmission is demonstrated with an extinction ratio of 4 dB.

Low loss 40 Gbit/s silicon modulator based on interleaved junctions and fabricated on 300 mm SOI wafers

We demonstrate high-speed silicon modulators based on carrier depletion in interleaved pn junctions fabricated on 300 mm-SOI wafers using CMOS foundry facilities. 950 µm-long Mach Zehnder (MZ) and ring resonator (RR) modulator with a 100 µm radius, were designed, fabricated and characterized. 40 Gbit/s data transmission has been demonstrated for both devices. The MZ modulator exhibited a high extinction ratio of 7.9 dB with only 4 dB on-chip losses at the operating point.

High extinction ratio 10 Gbit/s silicon optical modulator

High speed and high extinction ratio silicon optical modulator using carrier depletion is experimentally demonstrated. The phase-shifter is a 1.8 mm-long PIPIN diode which is integrated in a Mach Zehnder interferometer. 8.1 dB Extinction Ratio at 10 Gbit/s is obtained simultaneously with optical loss as low as 6 dB.

Analytical model for depletion-based silicon modulator simulation.

An original method to simulate depletion-based silicon modulators based on an analytical description of the active region is presented. This method is fast and efficient in particular for performance optimization. It is applied for a lateral diode integrated in a rib waveguide, and a comparison is performed with classical 2D numerical simulation. A very good agreement is obtained, showing the accuracy and efficiency of this analytical method.

40 Gb/s low-loss self-aligned silicon optical modulator

The silicon optical modulator is a key element in the advancement to meet the continuous demand on larger capacity of data transmission through optical interconnects, where the transmitted signal is required to have very low loss and large bandwidth. We present the experimental results of an all-silicon optical modulator based on carrier depletion in a lateral PIPIN diode. By embedding a p-doped slit in the intrinsic region of the PIN diode, the best compromise between effective index variation and optical loss in the middle of the waveguide is obtained. The PIPIN diode design guarantees a reduction of optical loss because large part of the waveguide is left unintentionally doped. Additionally, self-aligned fabrication was used to have an exact alignment of the active region, and to guarantee maximum modulation efficiency. At 40 Gb/s, the modulator delivered a 6.6 dB extinction ratio, with a 6 dB insertion loss at the operation point.

40 Gbit/s silicon modulators fabricated on 200-mm and 300-mm SOI wafers

We present 40 Gbit/s optical modulators based on different types of phase shifters (lateral pn, pipin, and interleaved pn junction phase). Those structures were processed both on 200 and 300mm SOI wafers, available in large-scale microelectronic foundries. Both Ring Resonators (RR) and Mach Zehnder (MZ) modulators were fabricated. As an example, MZ modulator based on 0.95 mm long interleaved pn junction phase shifter delivered a high ER of 7.8 dB at 40 Gbit/s with low optical loss of only 4 dB. Ring modulator was also fabricated and characterized at high-speed, exhibiting 40 Gbit/s.

High-speed silicon optical modulator based on a PIPIN diode

We present the experimental results of an error-free high-speed silicon optical modulator based on carrier depletion in a lateral 1.8 mm-long PIPIN diode embedded in a Mach-Zehnder interferometer. At 10 Gbit/s, the silicon optical modulator provides a large extinction ratio of 8.1 dB simultaneously with a low optical loss of 6 dB. The silicon modulator is a key element required to build and integrate photonic high performance data links.

Ring resonator silicon optical modulator based on interleaved PN junctions

We present first experimental results of a high-speed silicon optical modulator based on carrier depletion in interleaved PN junctions oriented in the waveguide direction. The modulator is integrated in a ring resonator of radius 50 μm. The modulator is characterized using a laser beam at 1.55 μm for TE and TM polarizations, and extinction ratios as high as 11 dB and 10 dB in in TE- and TM-polarizations, respectively, obtained between 0 and -10 V. At 10 Gbit/s extinction ratios of 4.1 dB and 2.7 dB for TE- and TM-polarization, respectively, are experimentally demonstrated.

High speed silicon modulators and germanium detectors

40Gbit/s optical modulators based on carrier depletion effect and germanium photodetectors integrated in silicon waveguides have been demonstrated at a wavelength of 1.55μm.