Silicon (Si) Wafers for Atomic Force Microscopy Research

What Silicon Used for Atomic Force Microscopy (AFM) Analysis

We have a large selection of high-quality, low cost silicon wafers to assist you in your AFM work.

What researchers need for AFM:

I am a PhD student. I want to order two types of wafers, the first type should have very smooth surface (silicon?) which can be used as the substrates for AFM or SEM analysis; the second type should not be conductive as I will deposit my materials onto the wafer for the conductivity measurement. No other specific requirements for other parameters.

Reference #223609 for specs and pricing.

Recently a client purchased 100mm P(100) 1-10 ohm-cm SSP 500um Prime Grade Wafers for AFM and various analysis.

Get Your Quote FAST! Buy Online and start researching today!

Thermal Oxide Coated Silicon for AFM Analysis

Researcher:

I am looking for 4” Si/SiO2 (300nm) wafer for microscopy (optical, AFM, SEM etc.) imaging of various materials.

Reference #192123 for pricing. Or buy Item #1432 online.

What Dry Oxide For Atomic Force Microscopy Analysis

I am reaching out to you from a university lab. I specialize in photoemission experimentson 2 dimensional (2D) material based devices. On these wafers I exfoliate 2D materials, create nano-scale devices, perform the following: electron transport, atomic force microscopy, Raman, electron beam lithography, Electron beam deposition, reactive ion etching, photoemission based experiments, and more.

Reference #249876 for specs and pricing.

Smooth Silicon Wafers For AFM

I am writing because our group is interested in the silicon wafers that you have. We plan to do a thin layer coating on the silicon wafer and check the properties of the coatings by using Atomic Force Microscopy (AFM), so the surface of the wafers should be very smooth, and I assume the size of the wafer should be in the range of several centimeter squares. Could you please advise me which silicon wafer you have could meet our requirements. The diameter should be around 2 inches (5 cm). We do not have specific requirement on the thickness. We want to purchase 10 pieces this time to test, and we might purchase more later if it works.

Reference #254362 for specs and pricing.

Checking Silicon Wafer Coating's Properties Using AFM

Reference #254362 for specs and pricing.

Test Grade Silicon for AFM Imaging

I am wondering if the silicon wafers 452 (100mm) are cut into segments for smaller samples or if it is just one 100mm wafer. I am trying to spin coat samples for AFM imaging and just need small wafers to mount the sample. Please let me know.

Reference #227035 for specs and pricing.

What Wafers are Suitable for Dropcasting Material onto for AFM Characterization?

A scientist requested the following quote:

I would like a quote for 2" silicon wafers. We looking for wafers suitable for dropcasting material onto for AFM characterization.

Reference #233351 for specs/pricing.

Atomic Force Microscopy Silicon

LearnThe Basics of Atomic Force Microscopy

Video: Basics of AFM

What Silicon Substrate is Used for Nanoparticle Morphology Characterization?

A postdoc requested a quote for the following:

We are finding diced silicon wafer chip. Basically, it can be pre-cut diced silicon chips or pre-slit 4" or 6" wafer that we can take them down piece by piece. The size we preferred is 10mmx10mm. The quantity we need is about 100 pieces. The Si grade can be testing grade, but no SiO2 on top of it; we just want to have a flat surface for sample coating for AFM and SEM characterization.

Reference #244781 for specs and pricing.

What Silicon Wafers are Used for AFM Imaging for Protein Samples?

A international Phd requested the following quote:

We have been purchasing 150mm Thermal Oxide Wafer. We laboratory has borrowed some plates for AFM imaging for protein samples. We has provided the link below to get it from your company. Can you please refer below and suggest the correct item you have shipped to his lab so we can get the same item as we have optimized the experiments?

Reference #246404 for specs and pricing.

What Silicon Substrates are Used for Scanning Probe Studies?

A Phd student I am was looking to buy nickel coated silicon substrates for conductive scanning probe studies.

I need the conductive wafer. I will run the AFM scanning experiment by using AFM conductive probe to touch on the human skin cell. My sample will be attached on the two side (upper and lower sides ) conductive wafer substrate. If you have oneside coated conductive wafer is fine for me.
At least it must be conductive because I will apply the positive voltage to the AFM tip and the negative voltage to the conductive wafer substrate to measure the potential across the cell sample. Can you please advise me with the different products?

Please give me info on the conductive wafer. I want the silicon wafer based with evapored conductive matter. may be copper and silver. I am doing AFM scan. So, I need vey smooth surface like 1 nm. What is smoothness of that wafer?

Reference #249330 for specs and pricing.

What Substrates are Used for AFM Measurements?

We are looking for 300mm Silicon wafers. The most important spec for us is its surface roughness (Rq), which ideally should be between 0.5~4 nm. Could you please provide me with a quotation if such wafer is available in your stock.

The most important spec is the surface roughness. Other specs, such as doping, thickness, resistivity, etc. are secondary. We mainly are looking for a relatively smooth and clean surface on a Silicon wafer (300 mm) in order to perform AFM measurements.

Reference # 254161 for specs and pricing.

What is Atomic Force Microscopy?

Atomic Force Microscopy (AFM) is a very special tool that scientists use to look at really, really tiny things.

You know how when you look at things with your eyes or a regular microscope, you can't see anything that's smaller than the tiniest little speck? Well, an AFM can actually help scientists see things that are much, much smaller than that!

An AFM works kind of like a little robot that uses a tiny tip to feel and touch the surface of whatever it's looking at. The tip is so small that it can even feel individual atoms!

By moving the tip around and feeling the surface, the AFM can make a picture of what the surface looks like. This helps scientists understand what things are made of and how they work on a really, really small scale.

What Substrates are Commonly Used?

Atomic force microscopy (AFM) can be used to image a wide variety of different materials and substrates. Some common substrates that are used in AFM experiments include:

Silicon wafers: These are flat, smooth surfaces that are often used as a reference surface for AFM experiments.
Mica: This is a mineral that can be cleaved to create a flat, smooth surface that is often used for imaging biological samples.
Glass: Glass slides are often used for imaging biological samples, as well as for other types of materials.
Metal surfaces: Many different types of metal surfaces can be imaged using AFM, including gold, silver, and copper.
Polymers: Polymers are large molecules that can be imaged using AFM, and are often used in materials science and nanotechnology.
Biological samples: AFM can be used to image biological samples such as proteins, DNA, and cells. In these cases, the sample is often mounted on a substrate such as mica or glass to make it easier to image.

There are many other types of substrates that can be used in AFM experiments, and the choice of substrate will depend on the specific research question and the type of sample being imaged.

Silicon Wafers Scientists Have Used for Atomic Force Microscopy (AFM)

Researchers have used the following wafers for their AFM research.

Item	Dia	Material	Orient.	Thick	Pol	res
1660	6"	N/As	[100]	675	SSP	0.001-0.005
SEMI TEST (spots & minor visual defects), 1Flat (57.5mm), Thermal Oxide 0.1μm±5% thick, Empak cst
1855	3"	P/B	[100]	380	SSP	44489
SEMI Prime, 2Flats, hard cst, DRY Thermal Oxide (5-7)nm thick, on both sides
6649	2"	N/As	[100]	380	SSP	0.001-0.005
SEMI Test, TTV<5μm, 1,000A oxide on both sides, wafers with visible dopant rings.
D925	5"	N/As	[100]	625	SSP	0.001-0.007
SEMI Prime, 2Flats, Thermal Oxide 3.5±0.5μm thick, Empak cst
E571	3"	N/Ph	[100]	381	SSP	44206
SEMI Prime, 1Flat, in Empak, Thermal Oxide
E683	5"	P/B	[111-3.5°] ±1.0°	375 ±15	SSP	0.012-0.018
Prime, 1Flat, Empak cst

Atomic Force Microscopy (AFM) Defined

Atomic force microscopy (AFM) has evolved as a powerful tool for mapping biological samples, including bacterial cells. It was also used for graphene imaging and development and allows the investigation and characterization of the graphene composite material. The ability to provide high-resolution images of a wide range of materials and objects, atomic force microscope or AF M, is the primary instrument used in research and industry to analyze materials or objects. [Sources: 0, 6, 9]

Scanning probe microscopy (SPM) comprises scanning tunneling, scanning electron microscope (SCM) and scanning surface imaging (SPI) techniques [26, 27], which are useful for the assessment of surface properties. AFM applications include the viewing of DNA and protein molecules that are applied to a coating that implants micronanoparticles, nanotubes and nanofibers. The atomic power microscope provides relevant nanomechanical information and clarifies relevant nanomechanical forensics and PSA studies by providing the possibility to document the effects of environmental conditions on PSEAs. [Sources: 1, 2, 3]

Similarly, we collected force curves from the bacterium - coated AFM tips and the corresponding images were represented by force distance curves generated by measuring the data by capturing and physically adsorbing the bacteria or by physical embellishment at the tip. In summary, the results of this study indicate that different methods of immobilization of bacteria by AF M influence the effects of AFM on the surface properties of nanofibers, nanotubes and silicones in different environments. The presence or absence of a particular force curve on a bacterial coated tip gave a different result than the presence of such a curve in a non-bacterial environment. [Sources: 9]

According to Flores and Toca Herrera, the atomic force microscope is certainly similar to a blind microscope, which can detect micro- and nanoobjects and can be easily compared with the behavior of a blind person, i.e. an AFM technique. The ability to measure the structure and observe sharp edges in atoms without real chemical bonds through AF M means that the mechanism of high-resolution imaging is worth investigating. [Sources: 4, 11]

The work compares the AFM interactions obtained from Klebsiella terrigena on silicon nitride with the commonly used immobilization methods for negatively charged bacteria on positively charged surfaces and negatively charged bacteria. The thesis compares three methods of immobilization: non-fibrillated oral streptococci, non-fibrillated and a combination of both. [Sources: 9]

The force spectroscopy measurements were performed with a fibrinogen functionalized tip on the surface of Klebsiella terrigena on silicon nitride. It was immediately mounted on an atomic force microscope and used for practical force spectroscopic sessions. H surface was determined by a scanning probe and the measurements of the force spectrum for the functionalization of the non-fibrillated oral streptococci were used by using an atomic thin layer of functionalizing fibreogen on a silicon oxide surface. [Sources: 8, 10]

The protrusions were made with different types of conductive tips that can be used in C - AFM, but the most successful were the conductors with diamond-coated silicon tips. The mechanical reaction between silicon and diamond was negligible and the rigid silicon outrigger that carries the diamond particles was produced, making the processing properties of silicon clearer. In addition to the functionalization of the non-fibrillated oral streptococci, we also used force spectroscopy measurements of Klebsiella terrigena on silicon nitride. [Sources: 2, 5]

This suggests that the MCP with a diamond tip in a radius of 100 nm is load dependent, as the shear stress exceeds the strength of silicon, including plastic deformations of several nanometers. Therefore, the interactions resulting from the mechanical reaction of Klebsiella terrigena on silicon nitride on positively charged glass are compared with the interactions between silicon and diamond tips. [Sources: 2, 9]

We will also discuss some important surface characterization techniques, consisting of scanning probe scanning, scanning tunnel and laser etching. First we investigate an AFM-based mechanical and mechanochemical process, followed by additional KOH solution etching. We use Kummali et al., 74 to investigate the interaction of Klebsiella terrigena on silicon nitride on positively charged glass with a diamond tip. [Sources: 2, 11]

Scanning, scanning and laser etching of Klebsiella terrigena on silicon nitride on positively charged glass with diamond tip. [Sources: 7]

Stretch, unfold and deform protein filaments that are adsorbed with an isolated piezoelectric boom. High-speed images with the atomic force microscopy of the walking myosin V with the tip of an atomic force microscope. High speed tapping and tapping: embellishing stretched, unfolded and deformed protein filaments with a silicon nitride - insulated insulator Z - insulator and an atomic force microscope with a laser etching process of a protein filament. [Sources: 4, 7, 10]

High-speed imaging with a conventional atomic force microscope that uses the non-contact mode of a silicon nitride insulator and a laser etching process on a protein thread. High-speed images with the scanning force microscope of the walking myosin V with an atomic force microscope. [Sources: 7]

By superimposing the surface model on the AFM images, we were able to further emphasize the fact that only hydrogenated silicon atoms are visible at some distance at the top of the sample. Although there does not seem to be a bond contrast to the silicon dimer bonds, the characteristics of the dimers in this region correspond to real chemical bonds. We understand that the presence of hydrogenate-silicon bonds in a silicon nitride insulator leads to the formation of a chemical bond between two silicon molecules. [Sources: 12]

Sources:

[1]: https://www.polymersolutions.com/blog/atomic-force-microscopy-imaging-and-lithography/

[2]: https://www.hindawi.com/journals/jnt/2014/102404/

[3]: https://www.intechopen.com/books/atomic-force-microscopy-and-its-applications/forensic-potential-of-atomic-force-microscopy-with-special-focus-on-age-determination-of-bloodstains

[4]: https://www.frontiersin.org/articles/10.3389/fchem.2019.00626/full

[5]: https://www.nrel.gov/materials-science/conductive-atomic.html

[6]: https://ldcn-mechatronics.net/on-chip-atomic-force-microscopy/

[7]: https://spie.org/news/3587-ultrashort-cantilever-probes-for-high-speed-atomic-force-microscopy

[8]: https://www.jstage.jst.go.jp/article/matertrans/58/3/58_M2016354/_html/-char/en

[9]: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC520872/

[10]: https://www.physiology.org/doi/full/10.1152/advan.00119.2014?url_ver=Z39.88-2003&rfr_id=ori:rid:crossref.org&rfr_dat=cr_pub%3Dpubmed

[11]: https://www.scielo.br/scielo.php?script=sci_arttext&pid=S0104-14282014000600006

[12]: https://www.nature.com/articles/ncomms14222

Research Papers Citing Atomic Force Microscopy

Here are five highly cited research papers on atomic force microscopy that have been influential in the field:

Binnig, G., Quate, C. F., & Gerber, C. (1986). Atomic force microscope. Physical Review Letters, 56(9), 930-933. This paper introduced the concept of the atomic force microscope and described its operation and potential applications.
Albrecht, T. R., Grütter, P., Horne, D., & Rugar, D. (1991). Frequency modulation detection using high-Q cantilevers for enhanced force microscope sensitivity. Journal of Applied Physics, 69(2), 668-673. This paper presented a technique for improving the sensitivity of atomic force microscopy by using high-Q cantilevers.
Garcia, R., & Perez, R. (2002). Dynamic atomic force microscopy methods. Surface Science Reports, 47(6-8), 197-301. This paper provided an overview of the different dynamic atomic force microscopy techniques and their applications, including non-contact AFM and frequency modulation AFM.
Radmacher, M., Fritz, M., & Hansma, P. K. (1994). Imaging adhesion forces and elasticity of lysozyme adsorbed on mica with the atomic force microscope. Langmuir, 10(11), 3809-3814. This paper demonstrated the ability of atomic force microscopy to measure the adhesion forces and elasticity of biomolecules, using lysozyme as an example.
Hoogenboom, B. W., Suda, T., & Dekker, C. (2007). Real-time observation of DNA translocation by the nanopore enzyme phi29 DNA polymerase. Nano Letters, 7(6), 1746-1750. This paper described the use of atomic force microscopy to observe the real-time translocation of DNA through a nanopore, which has important implications for DNA sequencing and biosensing applications.

What Substrate is Best for Sample Holders for Analytical Instruments?

A scientist requested the following:

I seek your product suggestion to collect my powder samples ready to use or transfer to microscopy please?

I have a large metal disc of 400mm diameter and is scored into 12 segments. Each segment will have very small amount of powder (less than a milligram) landing on it and I want to transfer from the disc (each segment) to either a SEM or AFM for analysis. Probably I will use fifty discs X 12 segments to give you an idea of the qty.

What type of product do you suggest and the lowest price alternative. Once I know I will make the order form you.

UniversityWafer, Inc. Replied.

It is common to use Silicon wafers as sample holders for analytical instruments. Silicon wafers are ultra pure, so they do not interfere with SEM analysis, They are ultra-clean so they do not contaminate even the smallest of samples. They are ultra-flat and of precise dimensions which is needed to introduce samples into AFM. Silicon wafers are cheaper than anything else with these properties. Without a drawing of your segmented collection disc and how you plan to transfer samples from it to the sample holder, I cannot specify the exact wafer that you need.

So rather, let me give you an outline of what is available. Silicon wafers come in sizes from 1"Ø to 6"Ø and larger. They come in thicknesses from 0.3mm to 1.0mm - thinner and thicker than above cost extra. As sample holders wafers are commonly diced into smaller squares, like 5×5mm or 20×25mm or whatever dimensions are required. Wafers also can be diced into equilateral triangles or regular hexagons or regular octagons.

They can also be diced into wedges or even pie shapes Silicon wafers can be one-side-polished or with both-sides polished. So you need to decide what wafer or diced sample holder dimensions you require, and if they are to be one-side-polished or double-side-polished.

You probably do not have to be concerned with wafers electrical properties. All monocrystalline, semiconductor grade silicon wafers with Resistivity > 1 Ohm-cm are more than adequately pure to be sample holders, p-type or n-type does not matter. Crystallographic orientation does not matter (except for sample holders for Powder X-Ray Diffraction). All semiconductor Silicon wafers come sealed in cassettes, cleaned to stringent cleanliness standards. Either specify the dimension of the sample holder that you require, or describe your apparatus in greater detail, and I shall provide you price quotes for what you need.

Reference #213585 for specs and pricing.

Can As-Cut Silicon Wafers Be Used for Atomic Force Microscopy?

A Phd requested help with the following project:

We have a project requiring the use of silicon as substrate of chips. We got to know that you are top in this field and want to order from you silicon wafers. However, we checked that usually silicon wafers are 100 mm in diameter which is too large for us, and we do not have any cutting tools for that. Wondering if it is possible to get as-cut specimens from you such as square or circular ones with a size of 10 mm? And how could us get a quotation?

Do you offer surface micropatterned wafer e.g. by photolithography? We would be very much interested if you have such product or service.

In addition, It is a little bit difficult for me to read your list as there are so many options. I am simply unsure about the selection of silicon regarding specifications such as p/n-type, polished, etched, oxide. My questions go like:

What are the differences and common applications for p and n type silicon?
What do you mean by “polished”? For those unpolished, are their surfaces good enough for use, for example in AFM testing?
What do you mean by “etched”? What kind of etching is that? When should I have this special surface treatment?
What are the surface oxides? Do you offer silicon substrate coated with different oxide species (besides SiO2)?

Maybe you could suggest one special type for us? Currently, we will use 10mm size wafer plates for creating array nanostructures (HF/AgNO3 etching) and doing surface functionalization for biosensing. I read in literature that people employ (100) Si, either p or n type and they often use Piranha solution or RCA solution for cleaning purpose.

UniversityWafer, Inc. Answered:

(q) Wondering if it is possible to get as-cut specimens from you such as square or circular ones with a size of 10 mm?
(a) Do you have any other requirements or just diameter? Can you accept any bigger size, like 15mm or 1"? What thickness? Do you need specimens made from c-Si or different material?

(q) we will need other specs later on. Do you offer surface micropatterned wafer e.g. by photolithography? W would be very much interested if you have such product or service.
(a) Please deliver design of the micropattern needed. We need to perform feasibility study first.

(q1). What are the differences and common applications for p and n type silicon?
(a1) The difference is in the conductivity type - property that identifies the majority charge carrier in the semiconductor. In n-type material the charge carriers are electrons and in p-type materials the charge carriers are holes. Common application for n-type is npn transistor and for p-type is pnp transistor.

(q2) What do you mean by “polished”? For those unpolished, are their surfaces good enough for use, for example in AFM testing?
(a2.1) The polished wafers have mirror-like surface, to achieve that they were subject of polishing process
(a2.2) It depends what would you like to test. I am familiar with roughness AFM tests. For the roughness tests they can be used.

(q3) What do you mean by “etched”? What kind of etching is that? When should I have this special surface treatment?
(a3) Before polishing any wafer there is wafers etching step. Popular etchants are KOH (alkaline) or HNO3+HF (acid). All polished wafers are etched before polishing.

(q4). What are the surface oxides? Do you offer silicon substrate coated with different oxide species (besides SiO2)?
(a4) Surface oxide is SiO2 layer formed on Si wafer. All oxides are SiO2.

(q5) Maybe you could suggest one special type for us? Currently, we will use 10mm size wafer plates for creating array nanostructures (HF/AgNO3 etching) and doing surface functionalization for biosensing. I read in literature that people employ (100) Si, either p or n type and they often use Piranha solution or RCA solution for cleaning purpose.
(a5) We would need to know more about the wafer you need. RCA (SC1, SC2) cleaning is the most common for Silicon. Piranha is common for other semiconductor materials. I am also familiar with Caro (H2SO4:H2O2) usage.

(q6) And how could us get a quotation?
(a6) Do you use silicon? Could you use bigger size wafers like 1" or 10mm is a must? What thickness do you need? Do you have any other requirements, specification maybe?

Researchers Investigate Gallium Nitride Using Atomic Force Microscopy

A graduate research assistant requested the following quote:

Bulk* GaN layer (~5um) on Silicon or Sapphire; not looking for GaN- combinations, just pure GaN. Wafer/Sample does not need to be large (< 2-in diam.). I am investigating GaN using atomic force microscopy. Before I found UniversityWafer.com, all the vendors of wafers that I could find offered only InGaAs, InGaN, AlGaN, AlN, etc. films on silicon or sapphire. This was frustrating, because I am looking for a wafer with a simple, undoped GaN film -- no other elements in it -- on the substrate. So, if this is what you term "free-standing GaN", then yes, this is what I'm looking for, and please forgive my lack of knowledge in not using this term instead.

Reference #103073 for specs and pricing.

How Does Atomic Force Microscopy Work?

Table 1: Outline of the Article

Introduction to Atomic Force Microscopy (AFM)
History and Development of AFM
- Invention and Early Stages
- Evolution and Advancements
Components and Design of AFM
- AFM Probe and Cantilever
- Laser and Photodetector
- XY Scanner and Sample Stage
The Working Principle of AFM
- Contact Mode
- Non-Contact Mode
- Tapping Mode
Applications of AFM
- Imaging and Surface Analysis
- Material Property Measurements
- Nanomanipulation and Nanofabrication
Advantages and Limitations of AFM
Conclusion and FAQs

Table 2: Article - How Does Atomic Force Microscopy Work?

Introduction to Atomic Force Microscopy (AFM)

Atomic force microscopy (AFM) is a high-resolution imaging technique that allows scientists to visualize and study surfaces at the nanoscale. It works by using a sharp probe to feel the surface of a sample and gather information about its properties, including topography, material properties, and even chemical composition. In this article, we will delve into the inner workings of AFM, its history, applications, and advantages and limitations.

**History and Development of AFM

Invention and Early Stages

AFM was invented in 1986 by Gerd Binnig, Calvin Quate, and Christoph Gerber as an advancement of the scanning tunneling microscope (STM). Unlike STM, which requires conductive samples, AFM has the ability to analyze a wide range of materials, including insulators, opening up new possibilities in the field of nanoscience.

Evolution and Advancements

Over the years, AFM has undergone numerous improvements and modifications, resulting in better resolution, increased imaging speed, and the development of various imaging modes. These advancements have broadened the scope of AFM applications and improved its performance in diverse research fields.

Components and Design of AFM

An AFM setup typically consists of the following key components:

AFM Probe and Cantilever

The AFM probe is a sharp tip, usually made of silicon or silicon nitride, mounted on a flexible cantilever. The probe is the main component responsible for sensing the surface properties of the sample. The cantilever acts as a spring, bending in response to the forces between the probe and the sample. The deflection of the cantilever is then measured to obtain information about the surface properties.

Laser and Photodetector

A laser is used to monitor the deflection of the cantilever. The laser beam is reflected off the backside of the cantilever and onto a photodetector. The photodetector records the position of the reflected laser beam, which changes as the cantilever bends. This information is used to construct an image of the sample's surface.

XY Scanner and Sample Stage

The XY scanner and sample stage are responsible for controlling the movement of the probe and the sample relative to each other. They provide precise positioning and enable scanning of the sample's surface in a raster pattern.

The Working Principle of AFM

There are three main imaging modes in AFM:

Contact Mode

In contact mode, the probe is brought into physical contact with the sample's surface. As the probe scans across the surface, the cantilever deflects due to the interaction forces between the probe and the sample. The deflection data is used to create a topographic map of the surface. Contact mode is best suited for imaging relatively flat surfaces and can provide high-resolution images.

Non-Contact Mode

In non-contact mode, the probe is positioned close to the sample's surface but does not make physical contact. Instead, it senses the long-range van der Waals forces between the probe and the sample. The cantilever oscillates at its natural resonance frequency, and changes in the oscillation frequency are used to generate an image of the surface. Non-contact mode is less invasive, reducing potential damage to both the probe and the sample.

Tapping Mode

Tapping mode is a hybrid of contact and non-contact modes. The cantilever oscillates at or near its resonance frequency, and the probe periodically taps the sample's surface. This mode provides a balance between the high-resolution imaging of contact mode and the reduced sample damage of non-contact mode.

Applications of AFM

AFM has a wide range of applications

Imaging and Surface Analysis

One of the primary applications of AFM is imaging surfaces at the nanoscale. Researchers use AFM to visualize and analyze the surface topography, roughness, and texture of various materials, including biological samples, polymers, and metals.

Material Property Measurements

AFM can be used to measure various material properties, such as mechanical properties (e.g., elasticity, stiffness), electrical properties (e.g., conductivity, capacitance), and magnetic properties (e.g., magnetization, magnetic domains). These measurements help scientists better understand the behavior of materials at the nanoscale.

Nanomanipulation and Nanofabrication

AFM is also employed for nanomanipulation and nanofabrication, where the probe can be used to manipulate individual atoms or molecules on a surface or to create nanostructures by depositing materials. This capability has implications for fields such as nanoelectronics and nanomedicine.

Advantages and Limitations of AFM

AFM offers several advantages over other surface characterization techniques, such as high resolution, the ability to analyze various materials, and minimal sample preparation requirements. Additionally, AFM can be performed in various environments, including air, vacuum, and liquids, enabling the study of samples under different conditions.

However, there are some limitations to AFM. The imaging speed can be relatively slow, especially for large samples, and the maximum scan range is limited by the size of the scanner. Also, interpretation of AFM data can be challenging due to the convolution of the probe shape with the sample's surface features.

Conclusion

Atomic force microscopy is a powerful and versatile technique for studying surfaces at the nanoscale. Its ability to image a wide range of materials and measure various properties has made it an indispensable tool in numerous research fields. Despite its limitations, AFM continues to be a valuable technique that provides insights into the nanoscale world, driving advancements in science and technology.

FAQs

What is atomic force microscopy (AFM)? AFM is a high-resolution imaging technique that uses a sharp probe to feel the surface of a sample and gather information about its properties, including topography, material properties, and chemical composition.
How does AFM differ from other microscopy techniques? AFM offers several advantages, such as high resolution, minimal sample preparation, and the ability to analyze various materials, including insulators. It can also be performed in different environments, such as air, vacuum, and liquids.
What are the main imaging modes in AFM? The main imaging modes in AFM are contact mode, non-contact mode, and tapping mode. Each mode has its specific advantages and applications.

What is AFM Roughness?

AFM roughness refers to the surface roughness measurement obtained using Atomic Force Microscopy (AFM). AFM is a high-resolution imaging technique that allows scientists and researchers to visualize and study surfaces at the nanoscale.

Surface roughness is a measure of the irregularities or variations present on a surface. AFM can be used to scan a sample surface with a sharp probe, which interacts with the surface and produces a topographic image. The probe moves across the surface, recording the height variations, and generates a three-dimensional representation of the surface topography.

AFM roughness analysis involves quantifying the height variations of the surface features. The roughness parameters are derived from statistical analysis of the height data, such as root mean square roughness (RMS), mean roughness (Ra), or average roughness (Rq). These parameters provide information about the average height deviations and the distribution of surface irregularities, which can be used to characterize the surface roughness.

AFM roughness measurements are particularly useful in fields such as materials science, nanotechnology, and surface engineering, where precise characterization of surface topography and roughness is important for understanding and optimizing material properties, studying surface interactions, or evaluating the effectiveness of surface treatments.

Indium Tim Oxide (ITO) - Float Zone Silicon - LiNbO3 - InGaAs - Nitride on Silicon - Aluminum - Silicon Carbide (SiC) - GaN on Sapphire