Kim Gyungock, Park Jeong Woo, Kim In Gyoo, Kim Sanghoon, Jang Ki-Seok, Kim Sun Ae, Oh Jin Hyuk, Joo Jiho, Kim Sanggi
Opt Lett. 2014 Apr 15;39(8):2310-3. doi: 10.1364/OL.39.002310.
We present small-sized depletion-type silicon Mach-Zehnder (MZ) modulator with a vertically dipped PN depletion junction (VDJ) phase shifter based on a CMOS compatible process. The fabricated device with a 100 μm long VDJ phase shifter shows a VπLπ of ∼0.6 V·cm with a 3 dB bandwidth of ∼50 GHz at -2 V bias. The measured extinction ratios are 6 and 5.3 dB for 40 and 50 Gb/s operation under 2.5 Vpp differential drive, respectively. On-chip insertion loss is 3 dB for the maximum optical transmission. This includes the phase-shifter loss of 1.88 dB/100 μm, resulting mostly from the extra optical propagation loss through the polysilicon-plug structure for electrical contact, which can be readily minimized by utilizing finer-scaled lithography nodes. The experimental result indicates that a compact depletion-type MZ modulator based on the VDJ scheme can be a potential candidate for future chip-level integration.
我们展示了一种基于互补金属氧化物半导体（CMOS）兼容工艺的、带有垂直浸入式PN耗尽结（VDJ）移相器的小型耗尽型硅马赫曾德尔（MZ）调制器。所制造的具有100μm长VDJ移相器的器件，在-2V偏置下，VπLπ约为0.6V·cm，3dB带宽约为50GHz。在2.5Vpp差分驱动下，40和50Gb/s操作时测得的消光比分别为6dB和5.3dB。最大光传输时的片上插入损耗为3dB。这包括1.88dB/100μm的移相器损耗，主要是由于通过用于电接触的多晶硅插塞结构的额外光传播损耗导致的，通过使用更精细尺度的光刻节点可以很容易地将其最小化。实验结果表明，基于VDJ方案的紧凑型耗尽型MZ调制器可能是未来芯片级集成的一个潜在候选方案。
