{"id":2173,"date":"2026-05-26T14:10:19","date_gmt":"2026-05-26T06:10:19","guid":{"rendered":"https:\/\/jeez-semicon.com\/?p=2173"},"modified":"2026-05-26T14:27:53","modified_gmt":"2026-05-26T06:27:53","slug":"surface-finish-standards-ra-grit-and-asme-bpe-explained","status":"publish","type":"post","link":"https:\/\/jeez-semicon.com\/de\/blog\/surface-finish-standards-ra-grit-and-asme-bpe-explained\/","title":{"rendered":"Surface Finish Standards Explained: Ra Values, Grit Chart, ASME BPE, and Semiconductor Metrics"},"content":{"rendered":"<!-- CLUSTER 6: Surface Finish Standards Ra Grit ASME BPE | JEEZ -->\n<style>\n.jz,.jz *,.jz *::before,.jz *::after{box-sizing:border-box}\n.jz{font-family:'Georgia','Times New Roman',serif;font-size:17px;line-height:1.85;color:#1a1a2e;max-width:860px;margin:0 auto;padding:0 20px 60px}\n.jz h2{font-family:'Trebuchet MS','Segoe UI',sans-serif;font-size:1.72rem;font-weight:700;color:#0a1628;margin:2.8rem 0 1rem;padding-bottom:.45rem;border-bottom:3px 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h1{font-size:1.6rem}.jz-cta{padding:28px 18px}}\n<\/style>\n\n<article class=\"jz\" itemscope itemtype=\"https:\/\/schema.org\/Article\">\n\n<div class=\"jz-hero\">\n  <div class=\"jz-hero-label\">Technical Reference<\/div>\n  \n  <p class=\"jz-hero-sub\">A complete technical reference for surface roughness parameters \u2014 Ra, Rq, Rz, WIWNU, TTV \u2014 with grit-to-Ra cross-reference tables, ASME BPE SF classification breakdown, and industry-specific surface finish requirements for semiconductor and pharmaceutical applications.<\/p>\n  <div class=\"jz-hero-meta\">\n    <span>Updated: May 2026<\/span>\n    <span>By JEEZ Engineering Team<\/span>\n    <span>~1,400 words<\/span>\n  <\/div>\n<\/div>\n\n<nav class=\"jz-toc\" aria-label=\"Inhalts\u00fcbersicht\">\n  <div class=\"jz-toc-title\">Inhalts\u00fcbersicht<\/div>\n  <ol>\n    <li><a href=\"#c6-params\">Surface Roughness Parameters Defined<\/a><\/li>\n    <li><a href=\"#c6-semiconductor\">Semiconductor-Specific Surface Metrics<\/a><\/li>\n    <li><a href=\"#c6-grit\">Grit-to-Ra Cross-Reference Table<\/a><\/li>\n    <li><a href=\"#c6-designations\">Industry Finish Designations<\/a><\/li>\n    <li><a href=\"#c6-asme\">ASME BPE Surface Finish Classification<\/a><\/li>\n    <li><a href=\"#c6-requirements\">Industry-Specific Requirements by Sector<\/a><\/li>\n    <li><a href=\"#c6-measurement\">Measurement Methods and Instrumentation<\/a><\/li>\n    <li><a href=\"#c6-faq\">H\u00e4ufig gestellte Fragen<\/a><\/li>\n  <\/ol>\n<\/nav>\n\n<p itemprop=\"description\">Surface finish standards are the common language between design engineers who specify polished surfaces and the process teams and suppliers who produce and verify them. Without a shared, unambiguous definition of &#8220;smooth,&#8221; specifications are open to interpretation and disputes. This reference article defines all major surface finish parameters used in semiconductor manufacturing, pharmaceutical equipment, and precision industrial fabrication, provides a comprehensive grit-to-Ra cross-reference, and explains the ASME BPE surface finish classification system in full. For the polishing process context, see our <a href=\"https:\/\/jeez-semicon.com\/de\/blog\/What-Is-Mechanical-Polishing-a-complete-technical-guide-for-semiconductor-manufacturing\/\" target=\"_blank\" rel=\"noopener\">complete mechanical polishing guide<\/a>.<\/p>\n\n<h2 id=\"c6-params\">1. Surface Roughness Parameters Defined<\/h2>\n<p>Surface roughness is measured by tracing a stylus (contact profilometer) or optical beam (non-contact profilometer) across the surface and recording the height profile z(x). From this profile, multiple statistical parameters are calculated over a defined evaluation length (typically 5 \u00d7 the cut-off wavelength \u03bbc per ISO 4288):<\/p>\n\n<div class=\"jz-table-wrap\">\n  <table class=\"jz-table\">\n    <thead><tr><th>Parameter<\/th><th>Symbol<\/th><th>Definition<\/th><th>Typical Use<\/th><\/tr><\/thead>\n    <tbody>\n      <tr><td><strong>Arithmetic Mean Roughness<\/strong><\/td><td>Ra<\/td><td>Average absolute deviation of the profile from the mean line over the evaluation length<\/td><td>Most widely used; stainless steel finishing, CMP process control<\/td><\/tr>\n      <tr><td><strong>Root Mean Square Roughness<\/strong><\/td><td>Rq (or RMS)<\/td><td>Square root of the mean of the squared deviations; more sensitive to peaks and valleys than Ra<\/td><td>Optical surface specifications; CMP wafer metrology<\/td><\/tr>\n      <tr><td><strong>Maximum Peak-to-Valley Height<\/strong><\/td><td>Rz<\/td><td>Average of the five largest peak-to-valley heights within the evaluation length<\/td><td>ASME BPE; DIN standards; corrosion and cleanability assessment<\/td><\/tr>\n      <tr><td><strong>Maximum Profile Height<\/strong><\/td><td>Rmax (Ry)<\/td><td>Single largest peak-to-valley height across the full evaluation length<\/td><td>Sealing surface specifications; bearing applications<\/td><\/tr>\n      <tr><td><strong>Skewness<\/strong><\/td><td>Rsk<\/td><td>Asymmetry of the profile height distribution; negative Rsk = more valleys (plateau surface)<\/td><td>Bearing surface characterization; tribological performance<\/td><\/tr>\n      <tr><td><strong>Kurtosis<\/strong><\/td><td>Rku<\/td><td>Sharpness of the profile height distribution; high Rku = spiky peaks<\/td><td>Wear prediction; sealing performance<\/td><\/tr>\n    <\/tbody>\n  <\/table>\n<\/div>\n\n<div class=\"jz-callout blue\">\n  <div class=\"jz-callout-title\">Ra vs. Rq Relationship<\/div>\n  <p>For a Gaussian (random) surface profile, Rq \u2248 1.25 \u00d7 Ra. However, real polished surfaces are often non-Gaussian \u2014 a freshly belt-ground surface with regular scratch marks has a more periodic profile where Rq\/Ra can be significantly different. Always specify which parameter is required; do not assume Ra and Rq specifications are interchangeable.<\/p>\n<\/div>\n\n<h2 id=\"c6-semiconductor\">2. Semiconductor-Specific Surface Metrics<\/h2>\n<p>In semiconductor manufacturing, wafer-level surface characterization uses additional metrics not commonly found in industrial surface finishing standards:<\/p>\n<ul>\n  <li><strong>WIWNU (Within-Wafer Non-Uniformity):<\/strong> Standard deviation of post-CMP film thickness across the 300 mm wafer, expressed as a percentage (1\u03c3%) of the mean thickness. Target: \u2264 2.5% for advanced node oxide and metal CMP.<\/li>\n  <li><strong>TTV (Total Thickness Variation):<\/strong> Difference between the maximum and minimum wafer thickness values across all measured sites. Specified for silicon wafer starting material; typically \u2264 0.5 \u00b5m for advanced logic prime wafers.<\/li>\n  <li><strong>Nanotopography:<\/strong> Spatial wavelength surface height variation in the 0.2\u201320 mm range, distinct from roughness (shorter wavelengths) and flatness (longer wavelengths). Nanotopography of the incoming silicon wafer influences STI CMP performance \u2014 high nanotopography can cause step-height variation that exceeds the CMP planarization length, leading to residual oxide non-uniformity.<\/li>\n  <li><strong>SFQR (Site Flatness Front Reference):<\/strong> Site-by-site flatness metric used for silicon wafer qualification; maximum deviation from a best-fit plane within a defined site window (e.g., 26 \u00d7 33 mm EUV exposure field). Typical SFQR specification: \u2264 40 nm for EUV-node wafers.<\/li>\n<\/ul>\n\n<h2 id=\"c6-grit\">3. Grit-to-Ra Cross-Reference Table<\/h2>\n<p>The relationship between abrasive grit number and achievable Ra is material-dependent and method-dependent. The values below represent typical achievable Ra on 316L stainless steel using aluminum oxide abrasives under normal polishing conditions:<\/p>\n<div class=\"jz-table-wrap\">\n  <table class=\"jz-table\">\n    <thead><tr><th>Grit No.<\/th><th>Avg. Particle Size (\u00b5m)<\/th><th>Typical Ra on SS (\u00b5m)<\/th><th>Finish Class<\/th><th>Anmeldung<\/th><\/tr><\/thead>\n    <tbody>\n      <tr><td>36<\/td><td>530<\/td><td>3.2 \u2013 6.3<\/td><td>As-ground rough<\/td><td>Heavy stock removal, weld cleanup<\/td><\/tr>\n      <tr><td>60<\/td><td>270<\/td><td>1.6 \u2013 3.2<\/td><td>Coarse grind<\/td><td>Remove deep pits and mill scale<\/td><\/tr>\n      <tr><td>80<\/td><td>200<\/td><td>1.0 \u2013 2.0<\/td><td>#3 Grinding<\/td><td>General fabrication cleanup<\/td><\/tr>\n      <tr><td>120<\/td><td>125<\/td><td>0.6 \u2013 1.2<\/td><td>#3\u20134 transition<\/td><td>Pre-#4 preparation<\/td><\/tr>\n      <tr><td>150<\/td><td>100<\/td><td>0.4 \u2013 0.8<\/td><td>#4 Brushed<\/td><td>3-A Sanitary, food contact surfaces<\/td><\/tr>\n      <tr><td>180<\/td><td>80<\/td><td>0.3 \u2013 0.6<\/td><td>#4 fine<\/td><td>ASME BPE SF1<\/td><\/tr>\n      <tr><td>220<\/td><td>65<\/td><td>0.2 \u2013 0.4<\/td><td>#6 Satin<\/td><td>ASME BPE SF1\u2013SF2<\/td><\/tr>\n      <tr><td>320<\/td><td>46<\/td><td>0.1 \u2013 0.2<\/td><td>#6\u20137 transition<\/td><td>Pre-buffing step<\/td><\/tr>\n      <tr><td>400<\/td><td>35<\/td><td>0.07 \u2013 0.15<\/td><td>#7 Buffed<\/td><td>ASME BPE SF2\u2013SF3; pre-electropolish<\/td><\/tr>\n      <tr><td>600<\/td><td>26<\/td><td>0.05 \u2013 0.10<\/td><td>#7 fine<\/td><td>Recommended pre-EP condition<\/td><\/tr>\n      <tr><td>800<\/td><td>21<\/td><td>0.03 \u2013 0.06<\/td><td>#7\u20138 transition<\/td><td>Pre-mirror buffing<\/td><\/tr>\n      <tr><td>1200<\/td><td>15<\/td><td>0.01 \u2013 0.03<\/td><td>#8 Mirror (pre-compound)<\/td><td>Optical and decorative mirror<\/td><\/tr>\n      <tr><td>Compound<\/td><td>0.5 \u2013 5<\/td><td>&lt; 0.025<\/td><td>#8 Mirror<\/td><td>Final mirror finish, mold cavities<\/td><\/tr>\n      <tr><td>CMP-Schlamm<\/td><td>12 \u2013 200 nm<\/td><td>&lt; 0.001 (1 \u00c5)<\/td><td>Semiconductor<\/td><td>Wafer planarization<\/td><\/tr>\n    <\/tbody>\n  <\/table>\n<\/div>\n\n<h2 id=\"c6-designations\">4. Industry Finish Designations<\/h2>\n<p>Multiple designation systems exist in parallel for stainless steel surface finishes. Engineers working across industries frequently need to translate between them:<\/p>\n<div class=\"jz-table-wrap\">\n  <table class=\"jz-table\">\n    <thead><tr><th>ASTM Designation<\/th><th>EN 10088 (European)<\/th><th>Common Name<\/th><th>Ra (\u00b5m)<\/th><th>Beschreibung<\/th><\/tr><\/thead>\n    <tbody>\n      <tr><td>#1<\/td><td>1D<\/td><td>Hot rolled, annealed<\/td><td>3.2 \u2013 12.5<\/td><td>Rough, dull; structural use only<\/td><\/tr>\n      <tr><td>#2B<\/td><td>2B<\/td><td>Cold rolled, bright<\/td><td>0.1 \u2013 0.5<\/td><td>Standard mill finish; most common<\/td><\/tr>\n      <tr><td>#3<\/td><td>1G<\/td><td>Grinding \/ rough polish<\/td><td>0.5 \u2013 1.6<\/td><td>Unidirectional scratch pattern, 80\u2013120 grit<\/td><\/tr>\n      <tr><td>#4<\/td><td>1J<\/td><td>Brushed finish<\/td><td>0.2 \u2013 0.8<\/td><td>Standard sanitary finish; 150\u2013180 grit<\/td><\/tr>\n      <tr><td>#6<\/td><td>\u2014<\/td><td>Satin (Tampico)<\/td><td>0.1 \u2013 0.2<\/td><td>Dull sheen; less directional than #4<\/td><\/tr>\n      <tr><td>#7<\/td><td>\u2014<\/td><td>Buffed<\/td><td>0.025 \u2013 0.1<\/td><td>High reflectance; pre-EP condition<\/td><\/tr>\n      <tr><td>#8<\/td><td>2P<\/td><td>Mirror<\/td><td>&lt; 0.025<\/td><td>True mirror; no visible grain<\/td><\/tr>\n    <\/tbody>\n  <\/table>\n<\/div>\n\n<h2 id=\"c6-asme\">5. ASME BPE Surface Finish Classification<\/h2>\n<p>The ASME BPE (Bioprocessing Equipment) standard defines a hierarchical Surface Finish (SF) classification specifically for stainless steel equipment used in biopharmaceutical and high-purity process industries. This system is also widely adopted in semiconductor equipment specification. The full SF classification:<\/p>\n<div class=\"jz-table-wrap\">\n  <table class=\"jz-table\">\n    <thead><tr><th>ASME BPE SF<\/th><th>Process<\/th><th>Max Ra (\u00b5m)<\/th><th>Max Rz (\u00b5m)<\/th><th>Additional Requirements<\/th><\/tr><\/thead>\n    <tbody>\n      <tr><td><strong>SF1<\/strong><\/td><td>Mechanically polished<\/td><td>0.84<\/td><td>\u2014<\/td><td>Minimum: #4 finish; visual inspection<\/td><\/tr>\n      <tr><td><strong>SF2<\/strong><\/td><td>Mechanically polished<\/td><td>0.51<\/td><td>\u2014<\/td><td>Profilometer Ra verification required<\/td><\/tr>\n      <tr><td><strong>SF3<\/strong><\/td><td>Mechanically polished<\/td><td>0.25<\/td><td>\u2014<\/td><td>Ra \u2264 0.25 \u00b5m; must be verified<\/td><\/tr>\n      <tr><td><strong>SF4<\/strong><\/td><td>Mechanically polished + electropolished<\/td><td>0.25<\/td><td>\u2014<\/td><td>EP after mechanical; Cr:Fe ratio verification<\/td><\/tr>\n      <tr><td><strong>SF5<\/strong><\/td><td>Electropolished<\/td><td>0.25<\/td><td>\u2014<\/td><td>EP only; enhanced Cr:Fe ratio; rouge resistance test<\/td><\/tr>\n      <tr><td><strong>SF6<\/strong><\/td><td>Electropolished + tested<\/td><td>0.25<\/td><td>\u2014<\/td><td>Full documentation; Cr:Fe \u2265 1.5; rouging qualification<\/td><\/tr>\n    <\/tbody>\n  <\/table>\n<\/div>\n\n<div class=\"jz-callout teal\">\n  <div class=\"jz-callout-title\">Key Distinction: SF3 vs SF4<\/div>\n  <p>Both SF3 and SF4 specify a maximum Ra of 0.25 \u00b5m \u2014 but they are fundamentally different surfaces. SF3 is a mechanically polished surface: chromium-depleted, with a cold-worked layer and potentially embedded abrasive. SF4 is mechanically polished followed by electropolishing: the cold-worked layer is removed, the Cr:Fe ratio at the surface is verified to exceed 1.5, and the surface exhibits significantly superior corrosion resistance and cleanability. For semiconductor process chemical systems, SF4 is the minimum specification for wetted surfaces.<\/p>\n<\/div>\n\n<h2 id=\"c6-requirements\">6. Industry-Specific Requirements by Sector<\/h2>\n<div class=\"jz-table-wrap\">\n  <table class=\"jz-table\">\n    <thead><tr><th>Industry \/ Application<\/th><th>Surface Material<\/th><th>Specification<\/th><th>Primary Standard<\/th><\/tr><\/thead>\n    <tbody>\n      <tr><td>Biopharmaceutical vessels<\/td><td>316L SS<\/td><td>Ra \u2264 0.25 \u00b5m; EP preferred<\/td><td>ASME BPE SF3\u2013SF4<\/td><\/tr>\n      <tr><td>Semiconductor CMP slurry systems<\/td><td>316L SS<\/td><td>Ra \u2264 0.25 \u00b5m; EP + passivation<\/td><td>ASME BPE SF4+<\/td><\/tr>\n      <tr><td>Semiconductor process gas delivery<\/td><td>316L SS tubing<\/td><td>Ra \u2264 0.25 \u00b5m ID; EP; no rouge<\/td><td>SEMI F20; ASME BPE SF4\u2013SF5<\/td><\/tr>\n      <tr><td>Food contact surfaces<\/td><td>304 \/ 316 SS<\/td><td>Ra \u2264 0.8 \u00b5m; #4 minimum<\/td><td>3-A Sanitary Standard 68; FDA 21 CFR<\/td><\/tr>\n      <tr><td>Semiconductor Si wafer<\/td><td>Silizium<\/td><td>Ra &lt; 0.1 nm; SFQR \u2264 40 nm<\/td><td>SEMI M1; JEIDA<\/td><\/tr>\n      <tr><td>Optical components (lithography)<\/td><td>Fused silica \/ ULE<\/td><td>Rq &lt; 0.05 nm; flatness &lt; \u03bb\/20<\/td><td>ISO 10110; customer spec<\/td><\/tr>\n      <tr><td>Injection mold (optical grade)<\/td><td>Hardened tool steel<\/td><td>Ra &lt; 0.01 \u00b5m<\/td><td>SPI A1; customer spec<\/td><\/tr>\n    <\/tbody>\n  <\/table>\n<\/div>\n\n<h2 id=\"c6-measurement\">7. Measurement Methods and Instrumentation<\/h2>\n<p>Surface finish measurement method selection must match the surface material and roughness range. Using the wrong instrument or settings is a common source of measurement errors in production environments:<\/p>\n<ul>\n  <li><strong>Contact profilometer (stylus):<\/strong> Gold standard for Ra measurement on metals. Stylus tip radius (typically 2 \u00b5m) limits the ability to resolve very fine features. Cutoff wavelength \u03bbc must be selected appropriately: ISO 4288 specifies \u03bbc based on the expected Ra range (e.g., \u03bbc = 0.8 mm for Ra 0.1\u20132 \u00b5m; \u03bbc = 0.25 mm for Ra 0.02\u20130.1 \u00b5m). Incorrect \u03bbc selection is a systematic measurement error.<\/li>\n  <li><strong>Optical profilometer (white-light interferometry \/ confocal):<\/strong> Non-contact; preferred for soft surfaces (Cu, Al), delicate components, and very smooth surfaces (Ra &lt; 10 nm) where stylus contact would damage the surface. Provides full 3D topographic maps (Sa, Sq, Sz \u2014 area-based equivalents of Ra, Rq, Rz).<\/li>\n  <li><strong>Atomic Force Microscope (AFM):<\/strong> Used for semiconductor wafer roughness measurement at the \u00c5 level. Provides Ra, Rq, and power spectral density (PSD) data at spatial wavelengths from 1 nm to 100 \u00b5m. Standard metrology tool for CMP wafer characterization in production and R&amp;D.<\/li>\n<\/ul>\n\n<div class=\"jz-callout amber\">\n  <div class=\"jz-callout-title\">Measurement Condition Standardization<\/div>\n  <p>Ra values measured under different conditions (different \u03bbc, different evaluation length, different stylus radius) are not directly comparable. When specifying or reporting Ra, always document: instrument type, stylus tip radius, cutoff wavelength \u03bbc, evaluation length, number of measurement traces, and trace locations on the part. This is required by ASME BPE Section SF for documentation compliance.<\/p>\n<\/div>\n\n<hr class=\"jz-divider\">\n\n<h2 id=\"c6-faq\">8. Frequently Asked Questions<\/h2>\n<div itemscope itemtype=\"https:\/\/schema.org\/FAQPage\">\n  <div class=\"jz-faq-item\" itemscope itemprop=\"mainEntity\" itemtype=\"https:\/\/schema.org\/Question\">\n    <div class=\"jz-faq-q\" itemprop=\"name\">What Ra value is required for pharmaceutical equipment?<\/div>\n    <div itemscope itemprop=\"acceptedAnswer\" itemtype=\"https:\/\/schema.org\/Answer\">\n      <p class=\"jz-faq-a\" itemprop=\"text\">ASME BPE specifies Ra \u2264 0.84 \u00b5m for SF1 (the minimum mechanical finish) through Ra \u2264 0.25 \u00b5m for SF3\u2013SF6. In practice, biopharmaceutical process equipment wetted surfaces are typically specified at ASME BPE SF3 (Ra \u2264 0.25 \u00b5m, mechanically polished) or SF4 (Ra \u2264 0.25 \u00b5m with electropolishing), depending on the product contact and cleaning validation requirements. Regulatory guidance from the FDA and EMA does not prescribe a specific Ra value but requires that surfaces can be validated as clean \u2014 electropolished surfaces at SF4 or above are far easier to validate due to their superior chemical inertness and reduced particle shedding.<\/p>\n    <\/div>\n  <\/div>\n  <div class=\"jz-faq-item\" itemscope itemprop=\"mainEntity\" itemtype=\"https:\/\/schema.org\/Question\">\n    <div class=\"jz-faq-q\" itemprop=\"name\">Is Ra the best parameter to specify for cleanability?<\/div>\n    <div itemscope itemprop=\"acceptedAnswer\" itemtype=\"https:\/\/schema.org\/Answer\">\n      <p class=\"jz-faq-a\" itemprop=\"text\">Ra is the most commonly used parameter for cleanability specifications, but it is not always the most informative. Ra measures average roughness amplitude but does not capture surface valley depth (Rz) or the lateral frequency of surface features \u2014 both of which influence bacterial adhesion and cleaning efficacy. For critical biopharmaceutical and semiconductor applications, specifying both Ra and Rz (or using 3D area-based parameters Sa and Sz from optical profilometry) provides a more complete surface characterization. ASME BPE SF4\u2013SF6 also requires Cr:Fe ratio verification by XPS or AES, recognizing that surface chemistry \u2014 not just roughness \u2014 governs corrosion resistance and cleanability.<\/p>\n    <\/div>\n  <\/div>\n<\/div>\n\n<hr class=\"jz-divider\">\n\n<h3>Related Technical Articles<\/h3>\n<div class=\"jz-related\">\n  <a class=\"jz-related-card\" href=\"https:\/\/jeez-semicon.com\/de\/blog\/What-Is-Mechanical-Polishing-a-complete-technical-guide-for-semiconductor-manufacturing\/\" target=\"_blank\" rel=\"noopener\">\n    <div class=\"jz-related-icon\">\ud83d\udcd8<\/div>\n    <div class=\"jz-related-title\">Complete Mechanical Polishing Guide<\/div>\n    <div class=\"jz-related-desc\">Full technical reference \u2014 principles, CMP process, materials, and industry applications.<\/div>\n  <\/a>\n  <a class=\"jz-related-card\" href=\"https:\/\/jeez-semicon.com\/de\/blog\/Mechanical-Polishing-of-Stainless-Steel:-Process-&\/#038;-Standards\" target=\"_blank\" rel=\"noopener\">\n    <div class=\"jz-related-icon\">\ud83d\udd29<\/div>\n    <div class=\"jz-related-title\">Stainless Steel Polishing<\/div>\n    <div class=\"jz-related-desc\">Grit sequences, work hardening management, and ASME BPE compliance for SS equipment.<\/div>\n  <\/a>\n  <a class=\"jz-related-card\" href=\"https:\/\/jeez-semicon.com\/de\/blog\/Mechanical-Polishing-vs-Electropolishing:-Key-Differences\/\" target=\"_blank\" rel=\"noopener\">\n    <div class=\"jz-related-icon\">\u26a1<\/div>\n    <div class=\"jz-related-title\">Mechanical Polishing vs. Electropolishing<\/div>\n    <div class=\"jz-related-desc\">How to sequence mechanical and electropolishing for maximum surface quality and compliance.<\/div>\n  <\/a>\n  <a class=\"jz-related-card\" href=\"https:\/\/jeez-semicon.com\/de\/blog\/Mechanical-Polishing-in-Pharmaceutical-&\/#038;-Food-Industries\" target=\"_blank\" rel=\"noopener\">\n    <div class=\"jz-related-icon\">\ud83e\uddea<\/div>\n    <div class=\"jz-related-title\">Pharmaceutical &amp; Food Industry Polishing<\/div>\n    <div class=\"jz-related-desc\">How ASME BPE surface finish requirements translate to CIP\/SIP process design.<\/div>\n  <\/a>\n<\/div>\n\n<div class=\"jz-brand\">\n  <div class=\"jz-brand-logo\">JEEZ<\/div>\n  <div class=\"jz-brand-text\">Published by the applications engineering team at <strong>Jizhi Electronic Technology Co., Ltd. (JEEZ)<\/strong> \u2014 manufacturer of CMP slurries, polishing pads, absorption films, and dicing blades for the semiconductor industry. Last reviewed: May 2026.<\/div>\n<\/div>\n\n<div class=\"jz-cta\">\n  <h2>Precision CMP Consumables Backed by Technical Expertise<\/h2>\n  <p>JEEZ supplies CMP slurries, polishing pads, and backing films with full lot documentation and applications engineering support. Contact us to discuss surface finish requirements for your process.<\/p>\n  <div class=\"jz-cta-btns\">\n    <a class=\"jz-btn primary\" href=\"https:\/\/jeez-semicon.com\/de\/contact\/\" target=\"_blank\" rel=\"noopener\">Request a Sample<\/a>\n    <a class=\"jz-btn outline\" href=\"https:\/\/jeez-semicon.com\/de\/contact\/\" target=\"_blank\" rel=\"noopener\">Talk to an Engineer<\/a>\n  <\/div>\n<\/div>\n\n<\/article>","protected":false},"excerpt":{"rendered":"<p>Technical Reference A complete technical reference for surface roughness parameters \u2014 Ra, Rq, Rz, WIWNU, TTV \u2014 with grit-to-Ra cross-reference tables, ASME BPE SF classification breakdown, and industry-specific surface finish  &#8230;<\/p>","protected":false},"author":1,"featured_media":2175,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[9,59],"tags":[],"class_list":["post-2173","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-blog","category-industry"],"acf":[],"_links":{"self":[{"href":"https:\/\/jeez-semicon.com\/de\/wp-json\/wp\/v2\/posts\/2173","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/jeez-semicon.com\/de\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/jeez-semicon.com\/de\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/jeez-semicon.com\/de\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/jeez-semicon.com\/de\/wp-json\/wp\/v2\/comments?post=2173"}],"version-history":[{"count":5,"href":"https:\/\/jeez-semicon.com\/de\/wp-json\/wp\/v2\/posts\/2173\/revisions"}],"predecessor-version":[{"id":2200,"href":"https:\/\/jeez-semicon.com\/de\/wp-json\/wp\/v2\/posts\/2173\/revisions\/2200"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/jeez-semicon.com\/de\/wp-json\/wp\/v2\/media\/2175"}],"wp:attachment":[{"href":"https:\/\/jeez-semicon.com\/de\/wp-json\/wp\/v2\/media?parent=2173"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/jeez-semicon.com\/de\/wp-json\/wp\/v2\/categories?post=2173"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/jeez-semicon.com\/de\/wp-json\/wp\/v2\/tags?post=2173"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}