{
  "abstract": "This work presents a surface-illuminated lateral Ge-on-Si interdigitated separate-absorption-charge-multiplication (SACM) avalanche photodiode for 1550-nm detection. The intrinsic-region spacing, P$^-$ charge-control width, and finger geometry are engineered to suppress high-field penetration toward the Ge/Si heterointerface and localize avalanche multiplication in Si. Simulations show that wider charge-control or intrinsic regions reduce fixed-bias dark current and shift avalanche onset to higher reverse bias. Among the tested structures, the intrinsic-region spacing/P$^-$ charge-control width of 0.5/0.15 $μ$m achieved a peak responsivity of 11.81 A/W at 1550 nm. At a -20 V applied voltage, it exhibited a multiplication gain of 3.796, a 3-dB bandwidth of 7.13 GHz, and a matched-bias gain-bandwidth product of 27.07 GHz. Optical-power-dependent measurements also show avalanche-gain compression consistent with space-charge screening. These results demonstrate effective lateral-field engineering for high-speed, surface-illuminated Ge-on-Si APDs.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2610.37593",
  "author_total": 4,
  "authors": [
    {
      "name": "Mason Clewis"
    },
    {
      "name": "Kuang-Yun Tu"
    },
    {
      "name": "Ching-Yu Hsu"
    },
    {
      "name": "Zingway Pei"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/8v0b8t4ng3y5x.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2610.37593",
  "fulltext_url": null,
  "id": "8v0b8t4ng3y5x",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2610.37593",
  "language": null,
  "licence": "LicenseRef-arXiv-nonexclusive-1.0",
  "licence_label": "arXiv licence",
  "licence_source": "article",
  "licence_url": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
  "metadata_licence": "CC0-1.0",
  "native_subjects": [
    [
      "arxiv",
      "physics.optics"
    ],
    [
      "openalex",
      "2208|Photonic and Optical Devices"
    ]
  ],
  "openalex": "W7224116677",
  "pdf_url": "https://arxiv.org/pdf/2610.37593",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-27",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/8v0b8t4ng3y5x.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:35:50Z",
      "native_id": "2610.37593",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2610.37593"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:physics.optics",
      "subfield": "optics-photonics"
    }
  ],
  "title": "Surface-Illuminated Interdigitated Ge-on-Si Avalanche Photodiode With Separated Ge Absorption, Si Multiplication, and Lateral Field Engineering",
  "title_text": "Surface-Illuminated Interdigitated Ge-on-Si Avalanche Photodiode With Separated Ge Absorption, Si Multiplication, and Lateral Field Engineering",
  "type": "preprint",
  "updated_at": "2026-10-30T12:35:50Z",
  "url": "https://research.draconitic.com/paper/8v0b8t4ng3y5x",
  "venue": "arXiv",
  "versions": []
}