{"id":4290,"date":"2026-03-20T08:25:41","date_gmt":"2026-03-20T08:25:41","guid":{"rendered":"https:\/\/saiweiglass.com\/?p=4290"},"modified":"2026-03-20T08:35:49","modified_gmt":"2026-03-20T08:35:49","slug":"ultra-thin-glass-types-materials","status":"publish","type":"post","link":"https:\/\/saiweiglass.com\/es\/blog\/ultra-thin-glass-types-materials\/","title":{"rendered":"Tipos y materiales de vidrio ultrafino: una gu\u00eda t\u00e9cnica para ingenieros y equipos de adquisiciones"},"content":{"rendered":"
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Choosing the wrong ultra-thin glass material can halt a line, ruin a display’s optical performance, or damage substrate warping in semiconductor processing. This guide explains the four main ultra-thin glass types and materials – borosilicate, aluminosilicate, soda-lime float, and fused silica – with real CTE values, thickness data, manufacturing context, and a straightforward matrix to match material with use. Whether defining glass for a foldable display, a biosensor, or an optical window, this guide helps you identify the correct specification at the outset.<\/p>\n

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Table of Contents<\/p>\n

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  1. What is ultra-thin glass and why does thickness matter?<\/a><\/li>\n
  2. Major Ultra-Thin Glass Material Types Compared<\/a><\/li>\n
  3. Properties affecting ultra-thin glass performance<\/a><\/li>\n
  4. How Ultra-Thin Glass Is Manufactured<\/a><\/li>\n
  5. Ultra-Thin Glass Applications Across Industries<\/a><\/li>\n
  6. Selecting the right ultra-thin glass for your project<\/a><\/li>\n
  7. Frequently Asked Questions<\/a><\/li>\n<\/ol>\n<\/div>\n

    <\/p>\n

    What Is Ultra-Thin Glass and Why Does Thickness Matter?<\/h2>\n

    \"What<\/p>\n

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    Definition<\/p>\n

    Ultra-thin glass<\/a> refers to glass substrates with thickness below 1.1 mm. The ultra-thin category is 0.1\u20130.5 mm, microsheet glass is under 0.1 mm (100 \u03bcm), and the thinnest commercial grade Schott D 263\u00ae T eco is 0.03 mm (30 \u03bcm). At 30 \u03bcm, that is thinner than a human hair.<\/p>\n<\/div>\n

    Thickness is a functional specification. It controls how the glass reacts under thermal cycling, its degree of motion under load, what manufacturing process can produce it, and what process handling system downstream demands. A substrate specified at 0.7 mm reacts completely differently from one at 0.2 mm, even where both are cut from the same borosilicate formulation.<\/p>\n

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    Industry Thickness Classification<\/p>\n

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    0.5\u20131.1 mm<\/p>\n

    Standard Thin Glass<\/p>\n<\/div>\n

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    0.1\u20130.5 mm<\/p>\n

    Ultra-Thin Glass<\/p>\n<\/div>\n

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    <0.1 mm<\/p>\n

    Microsheet \/ UTG<\/p>\n<\/div>\n

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    0.03 mm<\/p>\n

    Thinnest Commercial Grade (30 \u03bcm)<\/p>\n<\/div>\n<\/div>\n<\/div>\n

    In using ultra-thin glass substrates, we have seen thickness specification to be commonly defined first – and too often misunderstood. “The thinnest glass possible” specified without understanding thermal budget, process handling method, or tolerance range will often need to re-spec that specification as production planning progresses. Thickness determines the limit for every downstream decision: material family processability, drawing method tolerance control, and the viability of secondary operations.<\/p>\n

    Glass substrate families also overlap with display industry standards (sets by bodies such as IEC 62899 for flexible electronics) defining thickness tolerance ranges and surface quality grades. Locating your optical application within those categories helps guide selecting borosilicate or glass accordingly.<\/p>\n

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    Major Ultra-Thin Glass Material Types Compared<\/h2>\n

    \"Major<\/p>\n

    Four material families equate to most high-end ultra-thin glass substrate<\/a> applications. Each family balances CTE, optical transmission, chemical resistance, available thickness, and cost differently. The most appropriate is determined by your process environment, not your final product optical or mechanical needs.<\/p>\n

    Borosilicate Glass<\/h3>\n

    Borosilicate glass \u2014 brands include Schott BOROFLOAT\u00ae 33 and D 263\u00ae T eco \u2014 has a CTE of 3.25 \u00d7 10\u207b\u2076\/K and is available in the thinnest commercial formats. Its combination of low thermal expansion, high optical transmission (over 90% in visible, over 50% in near-UV), and strong chemical resistance makes it the default material for optics, sensors, and MEMS substrates.<\/p>\n

    D 263 T eco reaches 0.03 mm thickness, and is supplied up to 300 mm in sheet form. BOROFLOAT 33, float processed, can provide a wider thickness range, and larger panel formats. Both provide high chemical resistance to acids and bases, making them suitable for use with aggressive wet-clean chemistries employed in semiconductor fabrication.<\/p>\n

    Aluminosilicate Glass<\/h3>\n

    aluminosilicate glass<\/a> widespread use today is demonstrated by Corning’s eagle xg\u00ae and Willow, designed for use in display manufacturing, where alkali contamination of thin-film transistor (TFT) layers is unacceptable. Eagle XG, alkali free, has a CTE of ~3.17 \u00d7 10\u207b\u2076\/K, in thicknesses from 0.25 to 0.5 mm, and is produced in the standard display glass formats. Willow glass extends this still further, providing 100\u2013200 \u03bcm thickness in a roll form which allows pick and place reel-to-reel processing for flexible electronics.<\/p>\n

    For applications requiring chemical strengthening – such as cover glass for consumer electronics – aluminosilicate formulations respond better to the ion-exchange process than borosilicate. The higher alumina content creates a denser surface layer after potassium ion exchange, producing even deeper compressive stress depth, and higher surface compressive stress values. It is for this reason that chemically strengthened aluminosilicate glass is specified for use in UTG foldable display covers.<\/p>\n

    Soda-Lime Float Glass<\/h3>\n

    Soda-lime float glass, float processed on a molten tin bath, is the volumetrically highest of the cheapest. NSG’s UFF (Ultra Flat Float) grade takes the float process into thin glass formats at 0.33 mm and over. A CTE range of 8.5 to 9.0 \u00d7 10\u207b\u2076\/K – far higher than borosilicate or aluminosilicate, and therefore unsuitable for applications where precise thermal matching is required.<\/p>\n

    For cost-sensitive applications with established processing histories, soda-lime comes into its own. Thin soda-lime float glass has been a mainstay of the automotive industry for more than 40 years. Displays where TFT contamination is not critical, and where CTE mismatch with an adjacent layer is acceptable, also favor soda-lime in terms of material cost. Its high alkali content makes it unsuitable for many semiconductor processing environments without a barrier coating.<\/p>\n

    Fused Silica \/ Quartz<\/h3>\n

    Fused silica has the properties no other glass type can offer- CTE \u2264 0.5 \u00d7 10\u207b\u2076\/K; UV transmission of c.80% at 200 nm; thermal to 1,000C continuous service. These properties make it an ideal material for deep-UV lithography photomasks, UV optical windows, and high-power laser optics where soda-lime or borosilicate would be compromised by thermal shock or UV absorption.<\/p>\n

    The drawback is cost and ease of processing. Fused silica is a far more costly material to produce than borosilicate, more difficult to grind and polish, and the ultra-thin sheet format is less widely commercially available. For semiconductor photomask substrates, and precision UV optics, such costs are acceptable, but for general display or sensor applications it is rarely specified.<\/p>\n

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    \u26a0\ufe0f Common Specification Mistake<\/p>\n

    Often we see: borosilicate specified when the application actually calls for aluminosilicate, due to its alkali free processability. In a process with TFT deposition at over 400C, borosilicate’s Sodium content diffuses into the device layer, significantly reducing performance. Always verify whether your process is alkali-sensitive before specifying a glass family.<\/p>\n<\/div>\n

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    Material Comparison Table<\/p>\n

    \n\n\n\n\n\n\n\n\n
    Material<\/th>\nCTE (\u00d710\u207b\u2076\/K)<\/th>\nMin Thickness<\/th>\nUV\/Vis Transmission<\/th>\nKey Use<\/th>\n<\/tr>\n<\/thead>\n
    Borosilicate (BOROFLOAT\u00ae 33 \/ D 263\u00ae T eco)<\/td>\n3.25<\/td>\n0.03 mm (30 \u03bcm)<\/td>\n>90% (visible), >50% (near-UV)<\/td>\nOptics, MEMS, sensors, photomasks<\/td>\n<\/tr>\n
    Aluminosilicate (Eagle XG\u00ae \/ Willow\u00ae)<\/td>\n3.17<\/td>\n0.10 mm (100 \u03bcm)<\/td>\n>90% (visible)<\/td>\nDisplay TFT, foldable cover glass, UTG<\/td>\n<\/tr>\n
    Soda-Lime Float (UFF\u00ae by NSG)<\/td>\n8.5\u20139.0<\/td>\n0.33 mm<\/td>\n>88% (visible)<\/td>\nAutomotive, general display, cost-sensitive<\/td>\n<\/tr>\n
    Fused Silica \/ Quartz<\/td>\n\u22640.5<\/td>\n0.10 mm (custom)<\/td>\n>80% at 200 nm (UV)<\/td>\nUV lithography, laser optics, high-temp<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n

    Our supply chain works with all four material families. Our most common question from new clients is do I need aluminosilicate or borosilicate? In most cases the answer boils down to one question-do you have a process that deposits or diffuses at temperatures where alkali migration is relevant? If yes, aluminosilicate. Otherwise borosilicate will generally be more cost-effective for equivalent performance.<\/p>\n

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    Key Properties That Affect Ultra-Thin Glass Performance<\/h2>\n

    \"Key<\/p>\n

    Beyond material family, six core properties determine whether a thin glass materials<\/a> selection will be reliable in application. Each of the six properties for a given material selection is linked to a failure mode – neglect any single property and failure is possible both during assembly or in the field.<\/p>\n

    <\/p>\n

    \n\n\n\n\n\n\n\n\n\n\n
    Property<\/th>\nWhy It Matters<\/th>\nBorosilicate<\/th>\nAluminosilicate<\/th>\nSoda-Lime<\/th>\nFused Silica<\/th>\n<\/tr>\n<\/thead>\n
    CTE (\u00d710\u207b\u2076\/K)<\/td>\nThermal mismatch causes warping, delamination<\/td>\n3.25<\/td>\n3.17<\/td>\n8.5\u20139.0<\/td>\n\u22640.5<\/td>\n<\/tr>\n
    Optical Transmission<\/td>\nDisplay brightness, sensor signal, UV process efficiency<\/td>\nHigh (vis + near-UV)<\/td>\nHigh (vis)<\/td>\nGood (vis only)<\/td>\nExcellent (UV to IR)<\/td>\n<\/tr>\n
    Surface Quality \/ Flatness<\/td>\nLithography alignment, thin-film uniformity<\/td>\n<1 nm rms (down-draw)<\/td>\n<1 nm rms (fusion)<\/td>\n3\u20135 nm rms (float)<\/td>\n<1 nm rms (polished)<\/td>\n<\/tr>\n
    Chemical Resistance<\/td>\nWet process compatibility, cleaning solvent tolerance<\/td>\nHigh<\/td>\nHigh<\/td>\nModerate<\/td>\nExcellent<\/td>\n<\/tr>\n
    Flexibility (below 0.1 mm)<\/td>\nRoll-to-roll processing, foldable device design<\/td>\nLimited (>50 \u03bcm)<\/td>\nYes (Willow\u00ae 100 \u03bcm)<\/td>\nNot available <0.33 mm<\/td>\nNot available thin<\/td>\n<\/tr>\n
    Thermal Stability<\/td>\nHigh-temp deposition, reflow, laser processing<\/td>\nUp to ~500\u00b0C<\/td>\nUp to ~600\u00b0C<\/td>\nUp to ~450\u00b0C<\/td>\nUp to ~1,000\u00b0C<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n

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    \u26a0\ufe0f CTE Mismatch Warning<\/p>\n

    When using ultra-thin glass to bond a metal frame, ceramic carrier, or bonding substrate the glass coefficient of thermal expansion (CTE) must be considered relative to the thermal expansion coefficient of the carrier along the entire operation temperature range. A difference greater than 3 \u00d7 10\u207b\u2076\/K between soda-lime glass (CTE \u2248 9) and a silicon-based carrier (\u2248 2.6) will create enough strain to crack or delaminate the glass system during thermal cycling-this failure is well documented within the automotive HUD industry and MEMS packaging communities.<\/p>\n<\/div>\n

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    Our Property Evaluation Checklist<\/p>\n

    Prior to selecting any glass substrate we consider the following:<\/p>\n