Enhanced self aligned contact (SAC) etch stop window by using C/sub 4/F/sub 6/ chemistry

Wang, J.; Pu, Bryan; Bjokman, C.; Komatsu, Takeshi; Woo, JongRoul; Wang, Ruiping; Shan, H.

doi:10.1109/asmc.2001.925626

Cited by 4 publications

(5 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…21) In this current study, we focused on the C-CF bond ratio and investigated the effect of that ratio on the dielectric constant and thermal stability. Films prepared from C 4 F 8 , C 4 F 6 , and C 5 F 8 gases by using PECVD were compared because C 4 F 6 [22][23][24] and C 5 F 8 25,26) are expected to be substitutional gases due to their much lower GWP than C 4 F 8 .…”

mentioning

confidence: 99%

“…Here, the C-CF bond relative ratio was calculated by first deconvoluting the C 1s-XPS spectrum then dividing the peak intensity such as a previously reported procedure. 19,20,22,26) Figure 1 shows the Ar dilution dependency of C-CF bond ratio in the film prepared from C 5 F 8 plasma at a total flow rate (Ar and C 5 F 8 plasma) of 20 sccm. The C-CF bond ratio decreased with increasing Ar dilution ratio.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Source Gas Dependency of Amorphous Fluorinated Carbon Film Properties Prepared by Plasma Enhanced Chemical Vapor Deposition Using C₄F₈, C₄F₆, and C₅F₈ Gases

Watanabe

Shimogaki

2006

jjap

View full text Add to dashboard Cite

We have revised our earlier rough estimate of the combined galactic and extragalactic binary confusion noise level curve for gravitational waves. This was done to correct some numerical errors and to allow for roughly three frequency bins worth of information about weaker sources being lost for each galactic binary signal that is removed from the data. The results are still based on the spectral amplitude estimates for different types of galactic binaries reported by Hils et al in 1990, and assume that the gravitational wave power spectral densities for other galaxies are proportional to the optical luminosities. The estimated confusion noise level drops to the LISA instrumental noise level at between roughly 3 and 8 mHz.

show abstract

mentioning

confidence: 99%

mentioning

confidence: 99%

Source Gas Dependency of Amorphous Fluorinated Carbon Film Properties Prepared by Plasma Enhanced Chemical Vapor Deposition Using C₄F₈, C₄F₆, and C₅F₈ Gases

Watanabe

Shimogaki

2006

jjap

View full text Add to dashboard Cite

show abstract

“…However, increasing pressure induces etch stop. This may be due to less etchant reaching deep hole and less byproduct being pumped out from the hole [3]. WAT and CPAnalysis WAT for process scheme 2 with two CxFy based conditions were tested.…”

Section: Process Condition Parameter Effectsmentioning

confidence: 99%

Novel Deep SAC Etch Process Technology for Advanced FCRAM

Yang

Kim

et al. 2006

2006 IEEE International Symposium on Semiconductor Manufacturing

View full text Add to dashboard Cite

As scaling-down of COB type FCRAMTM (Fast Cycle RAM) approaches 0. lum, storage node self-aligned contact (SAC) presents the most critical problem for the integration. Small process window is one of the major problems for a deep SAC etch. By using CxFy based chemistry, a deep SAC etch process with higher SIN selectivity and wider etch stop window were achieved. This is quite beneficial for higher performance of advanced FCRAMTM.Introduction FCRAMTM is widely used in high-speed and low-power data transfer applications. Among Pseudo SRAM products, FCRAMTM provides ultra-high performance with low power and high speed. Because it uses a pipeline action not only for column access but also row access [1,2]. FCRAMTm has highly exacting specifications and unique process requirements, such as high refresh, high transistor performance, low standby current, low resistance and low parasitic capacitance of word lines (WL) and bit lines (BL). To achieve these special demands, a COB DRAM-like structure with novel deep SAC etch technology is needed due to the use of metal word line/bit line for obtaining lower parasitic capacitance, lower resistance and higher cell capacitance.This article describes CxFy based chemistry technology of deep SAC Etch for FCRAM applications. Experiment Two approaches of deep SAC structures for different capacitor schemes were implemented. Figure 1 shows one kind of schematic of the deep SAC process. Figure l.a is after Bit Line patterning, Figure l.b is after Bit Line Spacer formation. After ILD filling and CMP, nitride and top TEOS is deposited for future capacitor loop usage, and then the contact hole is patterned (Figl.c). Figure l.d shows the final cross section after deep SAC etching and PR stripping. It should be noted that every process step performance will affect future deep SAC etch performance and process window. Figure 2 is another process scheme. There is no Top nitride and TEOS deposition before photo patterning.Fig2. The schematic of deep SAC process 2 Based on these two schemes, we performed deep SAC etch experiments. CxFy A and CxFy B were used in the experiments.Within the 2 kinds of process schemes, CxFy A based chemistry has better etch stop margin than CxFy B based chemistry for process scheme 1. However, the bottom CD is small. For process scheme 2, CxFy B based technology can produce larger bottom CD than CxFy A while it also providing good etch stop margin.Therefore, process scheme 2-based chemistry deep SAC etch technology was chosen for the final WAT and CP yield test and produced good results.Results and Discussion There are two major issues which commonly arise in SAC etch. One is etch stop, another is Bit line to SAC short. Figure 3 shows these two issues, prior to etch recipe optimization. 145 S~~~~~|E .I (a)~~~~~~~~~(b):

show abstract

“…C 4 F 6 (hexafluoro-1,3butadiene) gas has a negligible GWP and a lifetime of approximately 2 days; thus, it is expected to be a substitutional gas. [22][23][24][25] In our previous work, we deposited a-C:F film from this C 4 F 6 by PECVD and investigated the relations between the density of C 4 F 6 in plasma and film properties. 26) From this study, we found that the density of C 4 F 6 affects the C-CF bond ratio and the C-CF bond affects the total dielectric constant.…”

Section: Introductionmentioning

confidence: 99%

Preparation and Characterization of Amorphous Fluorinated Carbon Film Using Low-Global-Warming-Potential Gas, C₄F₆, by Plasma-Enhanced Chemical Vapor Deposition

Watanabe

Shimogaki

2006

Jpn. J. Appl. Phys.

View full text Add to dashboard Cite

Low-dielectric-constant amorphous fluorinated carbon (a-C:F) films were prepared using plasma-enhanced chemical vapor deposition (PECVD) from C 4 F 6 (hexafluoro-1,3-butadiene) gas, which is expected to be a substitutional gas owing to its low global warming potential (GWP). Kinetic analysis revealed that the density of C 4 F 6 in plasma has a proportional relation to film growth rate, which suggests that C 4 F 6 is a main deposition precursor. From our previous study, this density affects the C-CF bond ratio in the film. In this study, we studied the effect of C-CF bond ratio on the thermal stability of the films by examining residual film thickness after vacuum annealing. A higher C-CF bond ratio resulted in a higher thermal stability, but the film became leaky after 300 C annealing.

show abstract

Enhanced self aligned contact (SAC) etch stop window by using C/sub 4/F/sub 6/ chemistry

Cited by 4 publications

References 0 publications

Source Gas Dependency of Amorphous Fluorinated Carbon Film Properties Prepared by Plasma Enhanced Chemical Vapor Deposition Using C₄F₈, C₄F₆, and C₅F₈ Gases

Source Gas Dependency of Amorphous Fluorinated Carbon Film Properties Prepared by Plasma Enhanced Chemical Vapor Deposition Using C₄F₈, C₄F₆, and C₅F₈ Gases

Novel Deep SAC Etch Process Technology for Advanced FCRAM

Preparation and Characterization of Amorphous Fluorinated Carbon Film Using Low-Global-Warming-Potential Gas, C₄F₆, by Plasma-Enhanced Chemical Vapor Deposition

Contact Info

Product

Resources

About

Enhanced self aligned contact (SAC) etch stop window by using C/sub 4/F/sub 6/ chemistry

Cited by 4 publications

References 0 publications

Source Gas Dependency of Amorphous Fluorinated Carbon Film Properties Prepared by Plasma Enhanced Chemical Vapor Deposition Using C4F8, C4F6, and C5F8 Gases

Source Gas Dependency of Amorphous Fluorinated Carbon Film Properties Prepared by Plasma Enhanced Chemical Vapor Deposition Using C4F8, C4F6, and C5F8 Gases

Novel Deep SAC Etch Process Technology for Advanced FCRAM

Preparation and Characterization of Amorphous Fluorinated Carbon Film Using Low-Global-Warming-Potential Gas, C4F6, by Plasma-Enhanced Chemical Vapor Deposition

Contact Info

Product

Resources

About

Source Gas Dependency of Amorphous Fluorinated Carbon Film Properties Prepared by Plasma Enhanced Chemical Vapor Deposition Using C₄F₈, C₄F₆, and C₅F₈ Gases

Source Gas Dependency of Amorphous Fluorinated Carbon Film Properties Prepared by Plasma Enhanced Chemical Vapor Deposition Using C₄F₈, C₄F₆, and C₅F₈ Gases

Preparation and Characterization of Amorphous Fluorinated Carbon Film Using Low-Global-Warming-Potential Gas, C₄F₆, by Plasma-Enhanced Chemical Vapor Deposition