Application
ELECTRICAL CHARACTERIZATION OF DIELECTRICS AND INTERFACES
Controlling electrical properties of dielectrics and the interfaces they form with semiconductors is imperative for achieving high IC device performance and yield. Semilab offers metrology solutions to electrically characterize the critical dielectric layers and processes that span process modules ranging from FEOL to BEOL.
The most common implementation of Semilab’s in-line electrical metrology is replacement of the IC MOS short-loop, which alleviates the need for expensive and time-consuming processing. The in-line methods provide rapid feedback without the need for preparing devices; resulting in increased process tool utilization time for critical product. The two primary MOS measurements being replaced are; 1) Capacitance – Voltage (C-V) method for determination of Dielectric Capacitance, Dielectric Charges, and Dielectric/Semiconductor Interface Quality; and 2) the Current – Voltage (I-V) method that measures Dielectric Leakage and Breakdown.
The below table summarizes the dielectric properties measured by Semilab systems, the associated critical IC device parameters that are affected, and the process areas in which the issues are commonly encountered.
Measured properties of dielectrics and interfaces:
| Measured Property | Affected Device Parameter | Process Module | |
|---|---|---|---|
| Dielectric/ Semiconductor Interface Quality (Dit, Qit, Nit) | Threshold voltage (Vt), Carrier Mobility, Reliability/ Hysteresis | Diffusion, Gate, Cleaning, |
ILD Plasma Thin Films |
| Dielectric Charge (Qf, Qm, Qot, Vfb) | Vt, Reliability/ Hysteresis | Diffusion Gate |
Plasma Thin Films |
| Dielectric Capacitance (CD, CET, EOT) | Vt, Reliability/ GOI, RC | Diffusion Gate |
ILD Thin Films |
| Surface Charge (VPDM, NVD, Vsurf) | Reliability/ GOI | Cleaning Plasma |
Thin Films Ion Implant |
| Dielectric Leakage (I-V, I-E, SILC, Etunnel) | Reliability/ GOI | Diffusion Gate Cleaning |
ILD Plasma |
In order to meet the individual requirements of our diverse customer base, Semilab offers various versions of these techniques using multiple approaches; including the non-contact Corona-Kelvin method (FAaST system) and the contact methods using Elastic Metal Probe (FCV system) and Mercury Probe (MCV system).