| 摘要 |
A semiconductor device comprises: a memory cell region having a first transistor and a peripheral circuit region having a second transistor. The first transistor has a first source electrode and a first drain electrode, a first buried gate insulating film which is formed along an inner wall of a trench and whose relative dielectric constant is higher than a relative dielectric constant of silicon oxide, and a buried gate electrode. The second transistor has a second source electrode and a second drain electrode, a first on-substrate gate insulating film whose relative dielectric constant is higher than a relative dielectric constant of silicon oxide, and an on-substrate gate electrode. A first Hf content percentage, which is a content percentage of hafnium in the first buried gate insulating film, is different from a second Hf content percentage, which is a content percentage of hafnium in the first on-substrate gate insulating film. |
| 主权项 |
1. A semiconductor device, comprising:
a memory cell region having a first transistor, and a peripheral circuit region which is formed around said memory cell region and has a second transistor, on a semiconductor substrate; wherein said first transistor has: a first source electrode and a first drain electrode which are formed on said semiconductor substrate, a first buried gate insulating film which is formed along an inner wall of a trench formed in said semiconductor substrate between said first source electrode and said first drain electrode and whose relative dielectric constant is higher than a relative dielectric constant of silicon oxide, and a buried gate electrode which is formed in said trench on said first buried gate insulating film, comprises metal and functions as a word line; and said second transistor has: a second source electrode and a second drain electrode which are formed on said semiconductor substrate, a first on-substrate gate insulating film which is formed on a surface of said semiconductor substrate between said second source electrode and said second drain electrode and whose relative dielectric constant is higher than a relative dielectric constant of silicon oxide, and an on-substrate gate electrode which is formed on said first on-substrate gate insulating film and comprises metal; said first buried gate insulating film and said first on-substrate gate insulating film comprising a compound containing hafnium, wherein a first Hf content percentage, which is a content percentage of hafnium in said first buried gate insulating film, is different from a second Hf content percentage, which is a content percentage of hafnium in said first on-substrate gate insulating film. |
