1. 半導體量測技術 Semiconductor Materials and Device Characterization Topic 2: measurement of doping profile Instructor: Dr. Yi-Mu Lee Department of Electronic Engineering National United University

2. Topics:measurements of doping profile C-V measurement serial circuit parallel circuit Band structure »equilibrium »with voltage applied I-V technology-- Threshold voltage (V T ) »How to derive (V T )? »Constant drain current (constant inversion charge) »Used in higher doping density samples All methods: limit, advantage/disadvantage

3. SRP: spreading resistance Pulsed MOS-C, MOSFET V T : changing V SB Suprem3: simulation results D. K. Schroder, p. 85

5. C-V Principle and C-V high/low freq curves:

7. Prev 3 slides from internet/website

8. I-V technology (V SB, V G method): (D. K. Schroder, section 2.3.1) -- MOSFET: V G, V DS (< 100mV) -- MOSFET: V BS (SCR extend into the substrate, allowing the doping density profile to be obtained) -- constant inversion charge density (constant drain current) how: adjusting V GS whenever V BS is changed -- affected by short-channel effect Equations: (2.25) and (2.26)using dV SB /dV GS

9. I-V technology:Threshold voltage -- DC technology -- V BS (negative: n-channel) (positive: p-channel) -- doping profile: measuring V T as a function of V SB (1)plotting V T against (2 ψF+V SB ) 1/2 (using 2ψ F =0.6ev) (2)measure slope γ -- affected by short-channel effect

10. Homework 4: 2.72.83.73.83.13 (students demonstrated/presented in class) Review suggested: Hall effect chapter 3:p.133~p.157 p.169~174 Preview suggested:chapter 4