Chemical categories
Hundreds of Formulations, Each Held to Its Own Tolerance
A leading-edge fab runs hundreds of acids, bases, solvents, resists, developers, slurries and plating chemistries to hundreds of tools. Purity, concentration, temperature and particle count at the nozzle set process repeatability: 0.1°C at a resist nozzle shifts coating thickness, and a 0.5% concentration drift in an acid shifts its etch rate.
- Acids, bases, oxidants
- Lithography chemicals
- CMP slurry
- Solvents
- Plating
| Category | Chemicals | Role | Purity and stability |
|---|---|---|---|
| Wet etch acids | HF; buffered oxide etch (HF/NH4F); H3PO4; HCl; H2SO4; HNO3 | Selective film removal; native oxide strip before gate dielectric | SEMI Grade 4-5; metals 1-10 ppb; concentration within 0.5%; temperature within 0.5°C |
| Bases and oxidants | NH4OH; H2O2; KOH; TMAH; SC-1; SC-2; SPM (piranha) | RCA cleans; resist strip; anisotropic silicon etch | H2O2 metals below 1 ppb; blends mixed at the tool so ratios hold |
| Photoresist and coat chemicals | ArF and EUV resists; BARC; TARC; spin-on carbon; spin-on glass; HMDS | Pattern definition; anti-reflection; hardmasks | EUV resist within 0.05°C at the nozzle; point-of-use filters below 0.02 µm |
| Developer | TMAH 2.38%; surfactant-modified EUV developers | Dissolves exposed or unexposed resist | 2.38% within 0.02%; temperature within 0.1°C |
| CMP slurries | Silica oxide slurry; ceria STI slurry; tungsten and copper slurries | Planarization; one slurry per film and stop layer | pH within 0.1; under 1% of particles above maximum size |
| Solvents and strippers | IPA; acetone; PGMEA; NMP; post-etch residue removers; ozonated UPW | Resist strip; residue removal; backside and chamber cleaning | Water content control; metals below 10 ppb; nitrogen-blanketed dispense |
| Electroplating | CuSO4, H2SO4 and HCl electrolyte with accelerator, suppressor and leveler | Copper dual-damascene fill | Additives within 5-10%, tracked by cyclic voltammetric stripping |
Delivery tiers
The Most Hazardous Handling Happens Farthest From the Wafer
Bulk handling sits at the fab perimeter, conditioning and distribution in the sub-fab, and only the final small-volume dispense reaches the wafer.
| Tier | Location | Function | Scale | Equipment |
|---|---|---|---|---|
| Bulk storage | Chemical building or tank farm at the fab perimeter | Stores, transfers and blends bulk chemical | 1,000-50,000 gallon tanks; two to four weeks of stock | HDPE, PP or FRP tanks; containment holding 110% of the largest tank; leak detection |
| Chemical management system | Sub-fab rooms, one per chemical class | Conditions chemical to spec and distributes it to tool clusters | 1-100 L/min per chemical per zone; dozens of units per fab | Concentration, temperature and particle sensors; 0.05-0.2 µm filters; heat exchangers |
| Point of use | At or inside the tool | Final filtration, temperature control and dispense | 1-30 mL per resist dispense; 100-500 mL/min per CMP platen | Bellows, diaphragm or syringe pumps; 0.01-0.2 µm filters; suckback nozzles |
Photoresist delivery
Photoresist Is the Most Demanding Chemical in the Fab
Resist viscosity changes about 2% to 5% per degree Celsius, coating thickness follows viscosity, and at EUV nodes thickness variation shows up directly as critical dimension (CD) variation. The delivery system holds temperature over 50 to 100 meters of tubing from bottle to nozzle.
| Parameter | EUV resist | ArF resist | Engineering |
|---|---|---|---|
| Temperature at dispense | Within 0.05°C | Within 0.1°C | Heat-traced lines; point-of-use temperature module; 0.01°C sensors |
| Particles at dispense | Under 5 per mL above 0.02 µm | Under 20 per mL above 0.05 µm | Filter just upstream of the nozzle; changed on differential pressure |
| Dispense repeatability | Within 0.5% of volume | Within 1% | Syringe or bellows pump with encoder feedback; suckback after dispense |
| Atmosphere | N2 on every container; N2-purged nozzle at some tools | N2 on containers | Sealed bottles with N2 overlay |
| Age and traceability | Shelf life under six months; stored at 0-10°C | Six to 12 months; 0-15°C | Lot tracking from bottle to wafer lot; quarantine on a temperature excursion |
CMP slurry delivery
CMP Slurry Can Never Stop Moving
A CMP slurry is a suspension of abrasive particles. When flow stops, particles settle and clump, and the clumps scratch the next wafers when flow resumes. Slurry loops recirculate around the clock, even when no wafer is being polished.
| Parameter | Requirement | If it slips | Control |
|---|---|---|---|
| Recirculation | Flow in every loop segment at all times, 0.3-1 m/s | Settling and agglomeration; scratches on the first wafers after restart | N+1 recirculation pumps; no dead legs; DI flush before and after any shutdown |
| Large particles | In-line large particle counters at several loop points | Automatic hold and loop flush | Particle Measuring Systems or Rion counters; point-of-use filter at the polisher |
| pH | Within 0.1 of setpoint | Faster agglomeration; removal rate and selectivity shift | In-line pH with automatic KOH or NH4OH correction |
| Dilution and oxidizer | Dilution within 1%; H2O2 added at the nozzle | H2O2 decomposes in the loop and cuts metal removal rate | Ratio blending; separate H2O2 injection for tungsten and copper CMP |
Safety
HF Sets the Safety Design
Hydrofluoric acid can kill through skin contact, concentrated oxidizers react violently with organics, and TMAH and NMP are toxic, so containment, detection and shutoff are designed in from the start.
| System | Function | Requirement |
|---|---|---|
| Leak detection | Gas and liquid sensors at every cabinet and chemical room, tied to tool interlocks | Floor sensors for heavy vapors, ceiling sensors for light; two alarm levels; under 30 seconds |
| Secondary containment | Bunds, drip trays and double-walled pipe | 110% of the largest container; acids and bases in separate zones; no open floor drains |
| Chemical exhaust | Negative-pressure exhaust to acid scrubbers and solvent carbon beds | Delivery shuts down on low exhaust; separate acid and solvent ducts |
| Emergency shutoff | Zone valves that close on leak, fire or seismic alarm | Fail closed; under five seconds; HF and Cl2 first |
| HF response | Calcium gluconate gel at every HF work area; trained responders | HF burns can cause hypocalcemia and cardiac arrest hours later; some fabs dilute to 1-5% at the tool and avoid storing 49% HF |
Piping materials
Piping Follows Chemistry, and Systems Never Share Headers
| Material | Handles | Fails on | Use |
|---|---|---|---|
| PFA, PTFE | Virtually all acids, bases, oxidizers and solvents | Molten alkali metals; elemental fluorine | Point-of-use tubing; resist lines; acid and base distribution |
| PVDF | Most acids at moderate concentration and temperature; H2O2 to 50% | Hot concentrated H2SO4; ketones such as acetone and MEK when hot; some amines | Bulk headers; acid drains; tank-to-sub-fab runs |
| Electropolished 316L stainless | Organic solvents; neutral solutions; UPW | HF; Cl2 and concentrated HCl; hot H2SO4; H2O2 above 30% | Solvent distribution |
| PP, FRP | Dilute acids and bases; wastewater | Hot concentrated acids; strong oxidizers; aromatic solvents | Drains; containment; neutralization and bulk tanks |
Qualification lock-in
Requalifying a Resist or Slurry Takes 12 to 18 Months
A delivery system is qualified to a specific resist or slurry formulation, so switching suppliers means requalifying the delivery components and the process. Resist changes take 12 to 18 months from introduction to volume approval, and CMP slurries about 18 months. That timeline, more than price, explains why process chemical supply diversifies slowly even when Japan's share of resist supply or China's localization push makes the case clear. Commissioning, leak testing and chemical qualification also run tool by tool on a new fab, which adding construction labor does not shorten.
Suppliers
Chemical Delivery and Chemical Suppliers
| Supplier | Base | Role |
|---|---|---|
| Entegris | Billerica, Massachusetts | Point-of-use filters; high-purity containers; PFA valves and fittings; CMP slurries and pads since buying CMC Materials for $6.5 billion in 2022 |
| Merck (EMD Electronics) | Darmstadt, Germany | Delivery systems from Versum Materials, including CHEMGUARD, plus solvents, high-purity acids and specialty chemicals |
| Kinetics | United States | Chemical management systems and process piping; subcontractor to Exyte and Jacobs on fab builds |
| Applied Energy Systems | Malvern, Pennsylvania | High-purity bulk chemical and gas delivery systems; active on US CHIPS Act fabs |
| JSR | Tokyo, Japan | ArF and EUV resists; taken private by the state-backed Japan Investment Corporation in 2024; owns Inpria metal-oxide EUV resist |
| Tokyo Ohka Kogyo (TOK), Shin-Etsu Chemical, Fujifilm | Japan | The rest of the leading resist supply base; Japanese firms hold most of world resist supply |
| Fujimi, Resonac, DuPont | Japan; Japan; United States | CMP slurries and pads alongside Entegris |
| Chinese suppliers | Jiangsu Nata Opto-electronic (resists); Anji Microelectronics (CMP slurries); Jianghua Micro-Electronics (wet chemicals) | Growing share at Chinese fabs as China localizes materials |
Record
Page Record
- Covers
- Chemical categories, delivery tiers, photoresist and CMP slurry delivery, safety systems, piping compatibility, qualification lock-in and suppliers
- Sources
- SEMI chemical grade guidelines; Entegris filings (CMC Materials acquisition, 2022); JSR and Japan Investment Corporation tender offer, 2024; Merck (Versum Materials acquisition, 2019); supplier product literature
- Last verified
- October 2026