Three-dimensional siloxane resist for the formation of nanopatterns with minimum linewidth fluctuations

Namatsu, Hideo; Takahashi, Yasuo; Yamazaki, Kenji; Yamaguchi, Toru; Nagase, Masao; Kurihara, Kenji

doi:10.1116/1.589837

Cited by 265 publications

(119 citation statements)

References 15 publications

Supporting

Mentioning

116

Contrasting

Unclassified

Order By: Relevance

“…Sub-10-nm isolated and dense features have been successfully fabricated using 100 keV EBL [59][60][61]. Low LER (below 2 nm) and high etch resistance (for single and bilayers) have been reported in several papers [22,59,62]. The properties of the resist (e.g.…”

Section: Overviewmentioning

confidence: 99%

“…The σ value (the root mean square (RMS) of the fluctuations in edge position) is the most frequently used parameter for characterization of LER. A typical measured value for LER is about 3 nm [22] or 10 nm (3σ ) [23], when resists with a very high contrast are used. The LER is caused by various factors which range from the lithographic system (dose fluctuation, mask roughness) to resist materials and the development process.…”

Section: Framework For the Nanofabrication Processmentioning

confidence: 99%

“…Namatsu [22] suggested that the development of HSQ in alkaline solutions is related to bond scission by ionization and that the dissolution rate strongly depends on the bond strength. At low exposure doses, the dangling Si bonds are not stable and the unexposed and slightly exposed areas close to the pattern are easily dissolved even when using a weak developer.…”

Section: Development Processmentioning

confidence: 99%

“…Still, in the last decade, HSQ (Flowable Oxide, FOx-12 from Dow Corning) has become a serious candidate for a high-resolution e-beam resist (see figure 16(b)) because of its small line edge roughness, high etching resistance and small molecular size [22]. HSQ is also an excellent resist for testing e-beam machine resolution limits because HSQ lines on silicon can be imaged directly in a SEM without the need for gold evaporation for conduction or 'lift-off' techniques [58].…”

Section: Overviewmentioning

confidence: 99%

“…A low dielectric constant lowers the capacitance between adjacent metal interconnects, reducing electrical delay and increasing the information processing rate of the device. In 1998 Namatsu et al [22] discovered that HSQ can be used as a negative tone resist for EBL. They suggested that the silicon hydrogen bonds (which are weaker than SiO bonds) are broken during e-beam irradiation and converted to silanol (Si-OH) groups in the presence of absorbed moisture in the film.…”

Section: Brief Introduction To Hsqmentioning

confidence: 99%

See 4 more Smart Citations

Resists for sub-20-nm electron beam lithography with a focus on HSQ: state of the art

2009

View full text Add to dashboard Cite

In the past decade, the feature size in ultra large-scale integration (ULSI) has been continuously decreasing, leading to nanostructure fabrication. Nowadays, various lithographic techniques ranging from conventional methods (e.g. photolithography, x-rays) to unconventional ones (e.g. nanoimprint lithography, self-assembled monolayers) are used to create small features. Among all these, resist-based electron beam lithography (EBL) seems to be the most suitable technique when nanostructures are desired. The achievement of sub-20-nm structures using EBL is a very sensitive process determined by various factors, starting with the choice of resist material and ending with the development process. After a short introduction to nanolithography, a framework for the nanofabrication process is presented. To obtain finer patterns, improvements of the material properties of the resist are very important. The present review gives an overview of the best resolution obtained with several types of both organic and inorganic resists. For each resist, the advantages and disadvantages are presented. Although very small features (2-5 nm) have been obtained with PMMA and inorganic metal halides, for the former resist the low etch resistance and instability of the pattern, and for the latter the delicate handling of the samples and the difficulties encountered in the spinning session, prevent the wider use of these e-beam resists in nanostructure fabrication. A relatively new e-beam resist, hydrogen silsesquioxane (HSQ), is very suitable when aiming for sub-20-nm resolution. The changes that this resist undergoes before, during and after electron beam exposure are discussed and the influence of various parameters (e.g. pre-baking, exposure dose, writing strategy, development process) on the resolution is presented. In general, high resolution can be obtained using ultrathin resist layers and when the exposure is performed at high acceleration voltages. Usually, one of the properties of the resist material is improved to the detriment of another. It has been demonstrated that aging, baking at low temperature, immediate exposure after spin coating, the use of a weak developer and development at a low temperature increase the sensitivity but decrease the contrast. The surface roughness is more pronounced at low exposure doses (high sensitivity) and high baking temperatures. A delay between exposure and development seems to increase both contrast and the sensitivity of samples which are stored in a vacuum after exposure, compared to those stored in air. Due to its relative novelty, the capabilities of HSQ have not been completely explored, hence there is still room for improvement.Applications of this electron beam resist in lithographic techniques other than EBL are also discussed. Finally, conclusions and an outlook are presented.

show abstract

Section: Overviewmentioning

confidence: 99%

Section: Framework For the Nanofabrication Processmentioning

confidence: 99%

Section: Development Processmentioning

confidence: 99%

Section: Overviewmentioning

confidence: 99%

Section: Brief Introduction To Hsqmentioning

confidence: 99%

See 3 more Smart Citations

Resists for sub-20-nm electron beam lithography with a focus on HSQ: state of the art

2009

View full text Add to dashboard Cite

show abstract

Fullerene Resist Materials for the 32 nm Node and Beyond

Gibbons

Robinson

Palmer

et al. 2008

Adv Funct Materials

View full text Add to dashboard Cite

Current resist materials cannot simultaneously meet the sensitivity, resolution and line width roughness (LWR) requirements set out by the International Technology Roadmap for Semiconductors (ITRS) for the 32nm node and beyond. Here we present a fullerene‐based, chemically amplified resist system, which demonstrates the potential to fulfill these requirements for next generation lithography. A chemically amplified fullerene resist was prepared, consisting of the derivative MF07‐01, an epoxide crosslinker, and a photoacid generator, such as triarylsulfonium hexafluoroantimonate. The sensitivity of this resist was shown to be between 5 and 10 µC cm−2 at 20 keV for various combinations of post‐application bake and post‐exposure bake conditions. Using 30 keV electron beam exposure, sparse patterns with 15 nm resolution were demonstrated, whilst for dense patterns a half‐pitch of 25 nm could be achieved. The LWR for the densely patterned features is ∼4 nm. The etch durability of the fullerene CA system was shown to be comparable to that of SAL601, a common novolac‐based commercial resist, at almost four times that of silicon.

show abstract

Two‐Dimensional Patterning of Flexible Designs with High Half‐Pitch Resolution by Using Block Copolymer Lithography

Yamaguchi

2008

Advanced Materials

View full text Add to dashboard Cite

A two‐dimensional patterning method that allows for flexible designs is demonstrated by combining bottom‐up diblock copolymer self‐assembly with top‐down electron beam lithography (EBL), which increases the applicability of block copolymer lithography to nanodevice fabrication. Both bent lamellae and concentric cylinders (see figure) can be formed between the intentionally designed 2D EBL guiding patterns, and can be successfully transferred to a semiconductor substrate with a 16 nm half‐pitch resolution.

show abstract

Three-dimensional siloxane resist for the formation of nanopatterns with minimum linewidth fluctuations

Abstract: Focused ion beam etching of resist/Ni multilayer films and applications to metal island structure formation

Cited by 265 publications

References 15 publications

Resists for sub-20-nm electron beam lithography with a focus on HSQ: state of the art

Resists for sub-20-nm electron beam lithography with a focus on HSQ: state of the art

Fullerene Resist Materials for the 32 nm Node and Beyond

Two‐Dimensional Patterning of Flexible Designs with High Half‐Pitch Resolution by Using Block Copolymer Lithography

Contact Info

Product

Resources

About