Abstract
Charge in HfO2 gate stacks grown from various metal-organic chemical vapor deposition sources has been studied using nMOS capacitors with a damage-free Cr gate process. It is found that the charge in the stack is mainly concentrated at the interfaces between materials. The effect of postdeposition anneal depends on the high-κ/ film-deposition chemistry. A forming gas anneal can reduce interface charge, hysteresis, and interface state densities for HfO2 films grown from various sources. The marked difference in the annealing response of similar films deposited from different precursors, however, strongly suggests that charge in these stacks is related to the deposition chemistry and may be due to residual impurities or defects left in the film from the deposition.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 448-450 |
| Number of pages | 3 |
| Journal | IEEE Electron Device Letters |
| Volume | 27 |
| Issue number | 6 |
| DOIs | |
| State | Published - Jun 2006 |
Bibliographical note
Funding Information:Manuscript received January 10, 2006; revised March 14, 2006. This work was supported by the Semiconductor Research Corporation under Contract 1060 and was performed at the Minnesota NanoFabrication Center, which receives partial support from the National Science Foundation through the NNIN Program. The review of this letter was arranged by Editor C.-P. Chang.
Keywords
- Annealing
- Charge
- Deposition
- HfO
- High-κ dielectrics
- Hysteresis
- Metal gate
- Stack