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V{OP¾Qj ¯¢iMÊ ¯Æ5i²PQ@_j ×ØV{¿ÀiRSTU¨E 2 V{¾Qjs³Á ¢Mi ¬ ²P Q_ jð 9: iV W wF {G ÛH
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õLPQ_iX¿À\H ( effective SiO2 thickness )
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¿¯ËiÈÊjG{s³´iÀð¯]^jG{s X\HùÀð¯ø_`G4'ij{ ( W ) ® ( WN ) ·Iij¿¯¢iX\H ùÀ;kial u Ii³´Pjõb ²PQ¼¶³´»jº¾V{cde<£ÁjgYï V¿À¡¢op×Ø
$ %&#'&
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Øjég25ðº¾i³Á¢N2O plasma annealing
shows no benefits in leakage reduction and slightly increase the effective
thickness. { ( W ) ® ( WN ) ·Ii
jsØMytu{GÛH ( N+-poly Si ) ·Ii
G N òi ( lá ij él s ³´P gõ ðh {G ÛH
( N+-poly Si ) ·Iiijb¼¶» ( SiO2 )
@£®@¢i°KL˱3²PQjðklop×Øyt Âmn¸à j{°±3¢«²PQkêë{£«Z[²PQ iRSk
( )*+,
1. Y. Ohji et al., “Ta2O5 capacitors’ dielectric material for giga-bit DRAM”, in IEDM Tech. Dig., p.111, 1995
2. L. K. Han, “Effects of post-deposition annealing on the electrical properties and reliability of ultrathin chemical vapor deposited Ta2O5 films”, IEEE Electron Device Lett., vol.15, p.280, 1994
3. S. Kmiyama et al., “Highly reliable 2.5nm Ta2O5 capacitor process technology for 256 Mbit DRAMs”, in IEDM Tech. Dig., p.827, 1991
4. G. Q. Lo et al., “Highly reliable, high-C DRAM storage capacitors with CVD Ta2O5 films on rugged polysilicon”, IEEE Electron Device Lett., vol.14, p.216, 1993
