FAQ ITO-Coatings
Frequently asked questions about our ITO-coated glass products
Back to the ITO coatings data sheet.
Here you will find the FAQ regarding our transparent conductive ITO-coated materials and ITO coatings in general. If you can't find an answer to your question, please feel free to contact us with your questions. We are pleased to share all available information with you.
• What is the microroughness of your ITO coatings?
• Do you stock any standard dimensions?
• Can you do custom dimensions?
• Which shape is more economical, round or rectangular?
• Can you do ITO with custom surface resistances?
• What is the typical delivery time for parts with custom dimensions?
• Can you coat other substrate materials than the ones listed?
• Can you coat ITO on the substrates that I supply?
• Can you coat plastics with ITO?
• Why can't I define the film thickness and the surface resistance at the same time?
• What is the technical difference between your CEC-S and CEC-P coatings?
• Can you make bus bars or offer options for contacting the ITO-coated surface?
• Do you make ready-made, heatable windows with wires connected?
• Do you make ITO-coated microscope slides?
• Do you have a price list for your ITO coatings?
• What is the thinnest possible substrate glass thickness?
• What is the transmission specification of your ITO coatings?
• Do you have transmittance or reflection curves?
• Can you manufacture index-matched ITO (IMITO)?
• What is the lowest and highest surface resistance you can coat?
• Where is the SiO2-passivation layer located, and what is its advantage?
• Do the SIO2 layers of the CEC-S and CEC-P coatings cause extra cost?
• Why are there coating types with an undefined (n/a) ITO film thickness in the table?
• Do you offer patterned or structured ITO coatings, patterning, or masking services?
All data and specifications given are average guide values and are not guaranteed.
Please consider our "Notes on technical specifications".
Q: What is the microroughness of your ITO coatings?
A: We know that the microroughness of the indium tin oxide coating is critical for some applications. However, inspecting the surface of every ITO-coated glass on the nanometer level is impractical. Therefore, we generally do not make a binding specification on the micro-roughness. If we specified the microroughness, we would have to do a 100% surface inspection with an atomic force microscope (AFM). Such an inspection would mean inspecting the complete surface area of each of the many million ITO-coated substrates and windows we make on the nanometer level. This kind of inspection, of course, is not feasible. However, many of our customers successfully use our ITO-coated materials for applications where micro-roughness is critical. We have typical AFM surface roughness test reports available for some of our CEC-P and CEC-S series coatings. We are pleased to share these test results with you on request. Please consider that these measurements are random snapshots taken from randomly selected production batches and do not present a specification.
Q: Do you stock any standard dimensions?
A: A significant advantage to our customers is that we, as a manufacturing company, are not limited to standard dimensions like most trading companies are. Almost every customer needs different part dimensions and must get the part size that fits his application. To be quick, even at custom sizes, we permanently make numerous ITO-coated materials, which you can find in this table. Please choose an ITO glass you are interested in, pick an available glass substrate thickness from the table, enter the size, and fill out our interactive request form. You are free to specify the dimensions! You usually receive our quotation the same day we receive your request. The typical delivery time for precision CNC-cut parts with customized dimensions made from any of the stock materials is 1-2 weeks, provided that the tolerances, the required manufacturing steps, or heavy production load do not require a longer lead time.
Q: Can you do custom dimensions?
A: Yes, of course! That's our specialty. Please send us your inquiry, and we will return a quotation for your custom-sized indium tin oxide-coated part, typically on the same day we receive your request.
Q: Which shape is more economical, round or rectangular?
A: Generally, rectangular shapes are more economical than round parts, especially in small quantities. This cost difference gets significantly more modest in large quantities, but the cost never ends up on the same level. Of course, this depends on the details, but a rectangular part with moderate tolerances is typically more economical compared to a round piece with identical tolerances.
Q: Can you do ITO with custom surface resistances?
A: Yes, we can. However, this is only possible on a per-coating batch basis, which means it is only an option if the number of parts is large enough for a custom coating run. It is impossible or too uneconomical for single pieces or small quantities. Small quantities would result in very high piece prices because the total coating run cost remains the same whether we coat one piece or the entire batch. If you want to know what quantity is required for a custom indium tin oxide coating batch, please send us your detailed request, and we will inform you about whatever is possible or reasonable.
Q: What is the typical delivery time for custom-sized ITO-coated windows or substrates?
A: This generally depends on tolerances, complexity, and the required manufacturing steps required to make your parts. Not least, it also depends on our production load. To give you an example, for precision CNC-cut square or rectangle parts with normal tolerances at average production load, the typical delivery time is less than a week!
Q: Can you coat other substrate materials with ITO than the ones listed?
A: Yes, this is possible only on a per-batch basis. In any case, it must be a suitable glass. We usually do not coat plastics. However, there are some exceptions that depend on the technical performance of the respective plastic material. If you want to get a special glass or plastic custom-coated with indium tin oxide, please contact us with your inquiry, and we will let you know the possible options.
Q: Can you coat ITO on the substrates that I supply?
A: Yes. Generally, we can custom coat customer-furnished material. A requirement is that your substrates are not already coated and are suitable to get ITO-coated. Please send us your inquiry with all the details. Please consider that this requires at least a full coating run.
Q: Can you coat plastics with ITO?
A: We usually do not coat plastics with indium tin oxide. However, exceptions depend on the technical performance of the plastic material. Please contact us with your inquiry.
Q: Why can't I define the film thickness and the surface resistance at the same time?
A: The specific surface resistance of a fully oxidized conductive ITO coating depends on the thickness of the indium tin oxide layer. It is therefore not possible to specify both parameters, the layer thickness and specific surface resistance, at the same time, as they are interdependent.
Q: What is the technical difference between your CEC-S and CEC-P coatings?
A: The only difference between the CEC-P and CEC-S coatings is that the CEC-P series' substrates are also mechanically polished. This additional polishing results in a lower total thickness variation (TTV) and better optical flatness. Simultaneously, it slightly increases the surface microroughness, resulting from the micro-scratches on the nanometer level that occur when a glass is mechanically polished, which is a natural effect. In other words, generally, the CEC-S coatings have a better (lower) surface microroughness, and the CEC-P coatings show a better TTV and optical flatness.
Q: Can you make bus bars or offer options for contacting the ITO-coated surface?
A: We do not make bus bars on our ITO coatings. However, as a service, we supply electrically conductive adhesive copper tape to the customers of our ITO-coated materials.
Q: Do you make ready-made heatable windows with wires connected?
A: No, but many customers use our ITO-coated materials to make their heatable windows or their heatable microscope slides.
Do you make ITO-coated microscope slides?
A: Yes, we do! We can make ITO-coated microscope slides of any size you want. Please choose an ITO-coated material you are interested in from the table here, click on an available glass substrate thickness, and please let us know the size and quantity of the microscope slide. We send you a detailed quotation in return, usually the same day we receive your request.
Q: Do you have a price list for your ITO coatings?
A: No. As a manufacturing company, we are not restricted to standard sizes and do not have a price list like trading companies. This flexibility is advantageous because you can specify and order the perfectly fitting dimensions you need for your application. Please select an ITO-coated material you are interested in from the chart here, pick an available glass thickness, and just let us know the dimensions and quantity you require. We send you a detailed quotation in return, usually the same day we receive your request.
Q: What is the thinnest possible glass substrate thickness?
A: The thinnest substrate thickness we can coat is approximately 0.175 mm. We always make an ITO-coated thin glass, which is called CEC020T. It has a square resistance of 20 Ω/sq. You might be able to use it when searching for thin, ITO-coated glass. Please refer to our chart here with all available resistances and glass thicknesses and send us an individual request. Also, custom coatings are possible, provided that the quantity is large enough for a coating run.
Q: What is the transmission specification of your ITO coatings?
A: This depends on the surface resistance and, therefore, on the ITO-film thickness. Moreover, the substrate material matters, and it depends on how well the glass substrate's refractive index matches the ITO-thin film's refractive index. You can find typical transmission curves for many of our transparent coatings here. If you need a characteristic transmission curve for an ITO coating not listed here, please do not hesitate to contact us and let us know what transmission curve you want to see.
Q: Do you have transmission or reflection curves available?
A: Yes. You can find typical transmission curves for many of our coatings here. We also have additional information on the transmission or reflection of many of our ITO-coated materials, which we can provide to you on request.
Q: Can you manufacture index-matched ITO (IMITO)?
A: Yes, but this is only possible on a per-coating batch basis per request, which means the quantity must be large enough for a custom coating run. It is impossible or too uneconomical for single pieces or small series. Please also consider that the top layer of an IMITO coating cannot be ITO because a layer on top of the ITO is required to adapt the refractive index to air in order to minimize the reflections. This top layer means that you cannot directly contact the ITO before removing the layer(s) on top.
Q: What is the lowest and highest surface resistance you can coat?
A: Generally, the lowest square resistance we coat is around 5 Ω per square and the highest is about 1000 Ω per square. We regularly make various coatings in this range (please refer to the chart here). If you need another square resistance, please send us your inquiry.
Q: Where is the SiO2 passivation layer located, and what is its advantage?
A: The SiO2 passivation layer is located between the glass substrate and the ITO-thin film. In other words, the quartz barrier layer separates the indium tin oxide layer from the glass surface. This quartz layer is only several nanometers thick and significantly increases the electrical insulation. At the same time, the layer minimizes the leaching of alkali oxides from the glass into liquid crystals, which is very function-critical for display applications. Only our CEC-S and CEC-P coatings have a SiO2 passivation layer. All other ITO coatings do not have a passivation layer. The SiO2-layer of our CEC-S and CEC-P coatings does NOT add any extra cost to our ITO-coated end product, as it is an integrated process and usually only has advantages.
Q: Do the SIO2 layers of the CEC-S and CEC-P coatings add extra cost?
A: The SiO2 layer of the CEC-S and CEC-P coatings does NOT add any extra cost to the ITO-coated end product, as it is an integrated process. It increases the technical product quality without raising the price. The CEC-S and CEC-P coatings are even our most economical ITO coatings, although they are the only ITO coatings with a standard passivation layer between the glass and the indium tin oxide.
Q: Why are there coating types with an undefined (n/a) ITO film thickness in the table?
A: We make all coatings without defined ITO-film thickness in a smaller coating machine. Those ITO coatings are mainly coated on more exotic glass substrate materials, and we don't make them in vast quantities like our CEC-S or CEC-P coatings, for example. Only the transmission and surface resistances are controlled in-situ in the smaller coating chambers during the coating process. The indium tin oxide film thickness is a result of these parameters and is not process-controlled. Therefore, we do not make specifications on the film thickness of these CEC coatings. Roughly put, the film thickness will be approximately in the range of the CEC-S or CEC-P coatings at the same surface resistivity.
Q: Do you offer patterned or structured ITO coatings, patterning, or masking services?
A: Sorry, no, we do not offer patterned ITO coatings or masking services at all. Our customers usually do the patterning themselves by etching away some areas of the ITO coating. For some of our ITO coatings, we give out typical non-binding etching recommendations on request. If you are interested in obtaining these, please contact us.
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Last update: April 22, 2025