Thin polyoxide on the top of poly-Si gate to suppress boron penetration for pMOS

Lee, Chung Len; Lei, Tan Fu; Chao, Tien Sheng

doi:10.1109/55.382227

IEEE Electron Device Lett.

1995

DOI: 10.1109/55.382227

|View full text |Cite

Thin polyoxide on the top of poly-Si gate to suppress boron penetration for pMOS

Chung Len Lee

Tan Fu Lei

Tien Sheng Chao

Help me understand this report

Search citation statements

Order By: Relevance

Paper Sections

Select...

Citation Types

Supporting

Mentioning

Contrasting

Year Published

1995

2019

Publication Types

Select...

Article6

Relationship

Self Cite0

Independent6

Authors

Journals

Cited by 7 publications

(1 citation statement)

References 4 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…1 Surface-channel devices exhibit a better threshold, subthreshold leakage control, and short channel effect control than those of the conventional buried-channel using the n ϩ -poly-Si gate for p-MOS-FETs. However, boron, coming from the BF 2 ϩ -implantation, penetrates easily from poly-Si gate through the gate oxide during the following high temperature thermal cycles at the presence of F. 2 To suppress the boron penetration, methods, such as the stacked poly-Si gate, 3 nitrided oxide, 4 oxide gettering, 5 and nitrogen coimplantation 6 have been reported. However, there is little report on the replacement of implantation source (BF 2 ϩ ) by the solid diffusion source.…”

mentioning

confidence: 99%

A Novel Si‐B Diffusion Source for p + ‐ Poly ‐ Si Gate

Chao¹,

Kuo

Chen

et al. 1999

J. Electrochem. Soc.

View full text Add to dashboard Cite

A p ϩ -poly-Si gate has been proposed for the fabrication of surface-channel p-metal oxide semiconductor field effect transistors (pMOSFETs) in deep submicrometer complementary MOS (CMOS). 1 Surface-channel devices exhibit a better threshold, subthreshold leakage control, and short channel effect control than those of the conventional buried-channel using the n ϩ -poly-Si gate for p-MOSFETs. However, boron, coming from the BF 2 ϩ -implantation, penetrates easily from poly-Si gate through the gate oxide during the following high temperature thermal cycles at the presence of F. 2 To suppress the boron penetration, methods, such as the stacked poly-Si gate, 3 nitrided oxide, 4 oxide gettering, 5 and nitrogen coimplantation 6 have been reported. However, there is little report on the replacement of implantation source (BF 2 ϩ ) by the solid diffusion source. The Si-B film that deposited in the ultrahigh vacuum chemical vapor deposition (UHV/CVD) system has been reported as the polycrystalline structure with extraordinary high B concentration (2 ϫ 10 22 /cm 3 ). 7 Hence, Si-B can be used as a solid diffusion source to form the p ϩ /n diode due to its high B concentration, and the smaller surface concentration and diffusivity. 8 These shallow junctions formed by the Si-B solid diffusion source exhibited better characteristics than those of conventional BF 2 ϩ -implanted junctions in terms of uniformity, ideality factor, and reverse current. In this paper, a novel Si-B layer, for the first time, is proposed as the solid diffusion source for doping the poly-Si as the p ϩ -poly-Si for p-MOSFETs to alleviate the boron penetration problem. It is found that this new process, which is free of F, depicts a better capability of suppressing the boron penetration than conventional methods employing BF 2 ϩ , or B ϩ implantation.Experimental p ϩ -Poly-Si gate MOS capacitors were fabricated on n-type Si(100) wafer with resistivity of 2-4 ⍀ cm. Field oxide, 550 nm, was grown and active areas were defined. A thin gate oxide 9.5 nm was grown at 900ЊC. A 300 nm poly-Si was then deposited. Samples with the conventional p ϩ -poly-Si gate were conducted by implanting BF 2 ϩ , 50 keV, to a dose of 5 ϫ 10 15 cm Ϫ2 ; or B ϩ , 20 keV, to a dose of 5 ϫ 10 15 cm Ϫ2 . While for the Si-B sample, they were put into a UHV/CVD system to deposit a 35 nm Si-B layer using a 1:1 mixture of the pure SiH 4 and B 2 H 6 (1% in H 2 ) at 550ЊC. The base pressure was 2 ϫ 10 Ϫ8 Torr. Afterward, all samples were annealed in a wet O 2 ambient at the temperature between 850 and 950ЊC for 15-35 min. Si-B layer was oxidized in this annealing process to form SiO 2 and the B diffused into the underlying poly-Si gate forming the p ϩ -poly-Si gate. The formed oxides were then dipped away. Al metal was deposited and patterned for contacts. After aluminum metallization, all samples were annealed at 400°C for 30 min in an N 2 ambient to form a good ohmic contact. The comprehensive effects on the annealing temperature (875-950°C) and time (15-35-min) on the p ϩ -In this pape...

show abstract

mentioning

confidence: 99%

A Novel Si‐B Diffusion Source for p + ‐ Poly ‐ Si Gate

Chao¹,

Kuo

Chen

et al. 1999

J. Electrochem. Soc.

View full text Add to dashboard Cite

show abstract

Nitridization of the stacked poly-Si gate to suppress the boron penetration in pMOS

Lai

Lee

Lei

et al. 1996

IEEE Trans. Electron Devices

View full text Add to dashboard Cite

NH3 -nitridation to create nitrogen-rich layers inbetween the stacked layers of the poly-Si gate for PMOS application is proposed and demonstrated. Due to the blocking of fluorine diffusion in the poly-Si gate by the nitrogen-rich layers, the amount of fluorine in the gate oxide, consequently, the fluorine enhancement on boron penetration is reduced. The negative effects of the NH3 -nitridized oxide were not found in this work. Moreover, this nitridized stacked poly-Si gate improves significantly the electrical characteristics of the gate oxide as a result of the indirect and slight nitridation at the gate oxide. Contract NSC84-22 15-E009-003.

show abstract

Nitridation of the stacked poly-Si gate to suppress the boron penetration in pMOS

Lai

Lee

Lei

et al. 1995

IEEE Electron Device Lett.

View full text Add to dashboard Cite

scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.

Contact Info

customersupport@researchsolutions.com

10624 S. Eastern Ave., Ste. A-614

Henderson, NV 89052, USA

This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.

Blog Terms and Conditions API Terms Privacy Policy Contact Cookie Preferences Do Not Sell or Share My Personal Information

Made with 💙 for researchers

Part of the Research Solutions Family.

Thin polyoxide on the top of poly-Si gate to suppress boron penetration for pMOS

Cited by 7 publications

References 4 publications

A Novel Si‐B Diffusion Source for p + ‐ Poly ‐ Si Gate

A Novel Si‐B Diffusion Source for p + ‐ Poly ‐ Si Gate

Nitridization of the stacked poly-Si gate to suppress the boron penetration in pMOS

Nitridation of the stacked poly-Si gate to suppress the boron penetration in pMOS

Contact Info

Product

Resources

About