1 / 17

半導體量測技術 Semiconductor Materials and Device Characterization

半導體量測技術 Semiconductor Materials and Device Characterization Topic 5: oxide trapped charge and poly-depletion effect in MOSFET Instructor: Dr. Yi-Mu Lee Department of Electronic Engineering National United University. Determine Q ot or Q m :. D. K. Schroder, p. 363.

gwyn
Download Presentation

半導體量測技術 Semiconductor Materials and Device Characterization

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. 半導體量測技術 Semiconductor Materials and Device Characterization Topic 5: oxide trapped charge and poly-depletion effect in MOSFET Instructor: Dr. Yi-Mu Lee Department of Electronic Engineering National United University

  2. Determine Qot or Qm: D. K. Schroder, p. 363

  3. effect on both sweeping direction Qot no effect has effect Qm D. K. Schroder, p. 363

  4. Finite gate doping density: Typical doping densities: 1019~1020/cm3 D. K. Schroder, p. 351

  5. Poly depletion effect on C-V curve (PMOS device): Why? D. K. Schroder, p. 351 Lf and hf C-V: both showing capacitance drop

  6. Poly depletion effects: • Change Vt • Reduce the drain current • Increase gate resistance 1~3: reduce circuit speed

  7. D. K. Schroder, p. 360 VFB-tox plot: determine work function and Qf

  8. D. K. Schroder, p. 361

  9. D. K. Schroder, p. 339

  10. D. K. Schroder, p. 340

  11. Fig 6.4 (a) D. K. Schroder, p. 341

  12. Fig 6.4 (b) and (c) (b) –Vg, surface: accumulated, Qp dominates, Cp is very high, so Cp, Cb, Cn, Cit are shorted (c) Small +Vg, depleted surface, Qb dominates Depletion to weak inversion Fig. from D. K. Schroder, p. 341

  13. Fig 6.4 (d) and (e) (d) Strong inversion: Cn can follow applied ac voltage, low-freq (e) Inversion charge can’t follow ac voltage, high-freq Fig. from D. K. Schroder, p. 341

  14. Interface trapped charge (Qit) • Low-freq (quasistatic) method • Effect of Qit on lf and hf C-V • acceptor-like and donor-like trap density

  15. High-freq CV Fig. from D. K. Schroder, p. 369 Qit doesnot contribute capacitance stretch-out due to gate-voltage axis Distorted C-V

  16. Low-freq CV Fig. from D. K. Schroder, p. 369 Donor-like trap Qit does contribute capacitance acceptor-like trap inversion delay additional capacitance: Qit respond low-frequency

  17. Review: • P. 346 (exercise 6.1) • Band structure (equilibrium, non-equilibrium) • P. 368~372 • Derive eq (6.44) and (6.47)

More Related