Title :
Hot-carrier-induced degradation of gate dielectrics grown in nitrous oxide under accelerated aging
Author :
Ditali, Akram ; Mathews, Viju ; Fazan, Pierre
Author_Institution :
Micron Semicond. Inc., Boise, ID, USA
Abstract :
Gate oxides grown with partial and complete oxidation in N/sub 2/O were studied in terms of hot-carrier stressing. The DC lifetime for 10% degradation in g/sub m/ had a 15*improvement over control oxides not grown in a N/sub 2/O atmosphere. Further improvement in g/sub m/ degradation was observed in oxides that received partial oxidation as compared with control oxides. This improvement is due to the incorporation of nitrogen that reduces strained Si-O bonds at the Si/SiO/sub 2/ interface, leading to lower interface state generation (ISG). Improvements were also observed in I/sub g/-V/sub g/ characteristics, indicating a reduction of trap sites both at the Si/SiO/sub 2/ interface and in the bulk oxide. Improved gate-induced drain leakage (GIDL) characteristics as a function of hot-carrier stressing for partial N/sub 2/O oxides were observed over control oxides. However, severe drain leakage that masked GIDL was observed on pure N/sub 2/O oxides and is a subject for further study.<>
Keywords :
ageing; dielectric thin films; hot carriers; insulated gate field effect transistors; life testing; metal-insulator-semiconductor structures; reliability; DC lifetime; GIDL; N/sub 2/O atmosphere; Si-SiO/sub 2/; Si/sub x/N/sub y/O/sub z/ thin films; accelerated aging; complete oxidation; gate dielectrics; gate-induced drain leakage; hot carrier induced degradation; hot-carrier stressing; interface state generation; partial oxidation; reduction of trap sites; Accelerated aging; Degradation; Dielectrics; Furnaces; Hot carriers; Interface states; Nitrogen; Oxidation; Stress control; Thickness control;
Journal_Title :
Electron Device Letters, IEEE