Demo SiliconWorks: semiconductor fab operations day

Demo SiliconWorks manufactures power-management chips in a 300 mm fab in Abu Dhabi and assembles finished devices in Malaysia. It buys high-purity chemicals and wafers, runs hundreds of process steps, tracks yield and rework, maintains expensive equipment, and sells tested lots in USD and EUR. OSERP connects production recipes, wafer lots, cleanroom inventory, equipment, quality holds, customer orders, supplier certificates, and finance.

1. Create products, recipes, and lot controls

The product master stores device code, revision, package, die size, UoM, planning lead time, yield target, quality plan, revenue account, COGS account, and active dates. Recipe versions record process step, tool family, material, quantity, tolerance, cycle time, operator qualification, and effective date. Lot profiles store wafer ID, supplier, certificate, thickness, resistivity, moisture, and expiry.

Field	Demo value	Impact
Device	SW-PM45A	Customer and revenue identity
Revision	R3	Recipe and quality scope
Wafer lot	WAF-260917-048	Genealogy and yield
Diameter	300 mm	Equipment compatibility
Grade	Prime	Price and disposition
Yield target	92%	Variance and forecast
Currency	USD	Sales and cost settlement
Cleanroom class	ISO 5	Handling and access

An approved recipe cannot be edited in place. A new revision requires engineering approval, effective date, and qualification evidence.

2. Receive wafers and cleanroom materials

Purchase receipts record supplier, purchase order, wafer lot, quantity, UoM, certificate, shipment, temperature, cleanroom entry, and inspection. Chemical lots store concentration, container, hazard class, expiry, storage location, and safety data sheet. Quarantine stock is unavailable until lab release.

Incoming inspection records thickness, flatness, particle count, resistivity, sample plan, instrument, result, inspector, and disposition. A failed lot remains traceable to supplier, receipt, and any affected work order; it cannot be silently scrapped.

3. Plan lots and execute process steps

The lot work-order header records product revision, wafer lot, route, quantity, start date, priority, customer allocation, cleanroom, and status. Step lines record operation, tool, recipe version, operator, start/end, parameters, materials, scrap, rework, and sign-off.

For WAF-260917-048, 25 wafers enter lithography and etch. Each step captures pressure, temperature, gas flow, exposure dose, and tool ID. A parameter outside tolerance creates a hold and deviation; the lot cannot proceed without engineering disposition.

4. Measure yield, scrap, and rework

Inspection results store lot, wafer, die map, test programme, defect code, severity, sample, instrument, and result. Yield is calculated from good dies divided by tested dies, with target, confidence, and revision. A 90.5% yield against a 92% target creates a corrective-action work item.

Rework records original step, reason, approved route, additional materials, time, risk, and final result. Scrap records quantity, defect, value, witness, environmental method, and approval. Costing preserves original and rework cost separately.

5. Maintain fab equipment and utilities

Equipment assets store tool ID, chamber, manufacturer, commissioning date, cost, useful life, depreciation book, calibration, qualification, cleanroom, and uptime target. Maintenance orders record failure mode, permit, technician, parts, gases, downtime, calibration, test wafer, and return-to-service approval.

Utilities readings contain tool, period, electricity, water, gas, cleanroom load, tariff, currency, and allocation basis. Preventive maintenance due dates block dispatch to an unqualified tool. Critical-spare issues link part serial, work order, tool, and technician.

6. Sell finished lots and manage customer quality

Sales orders record customer, device revision, qualification, currency, Incoterm, delivery date, price list, credit status, and approval. Lines record finished lot, quantity, test grade, packaging, traceability, and unit price. A USD customer order for 10,000 devices reserves released lots only.

Delivery records container, seal, lot, quantity, carrier, export document, and proof of delivery. Customer returns and quality claims reference device, lot, failure analysis, containment, credit, and corrective action. A lot with an open critical complaint is blocked from further shipment.

7. Trace suppliers, compliance, and customer commitments

Supplier certificates store material, lot, standard, test, issue/expiry, laboratory, and evidence hash. Conflict-minerals, restricted-substance, export-control, and customer qualification records store declaration, territory, reviewer, and expiry. A shipment cannot release while required evidence is missing.

Customer allocation records committed lot, forecast, promise date, priority, currency, and change reason. Short supply creates an approved allocation decision rather than invisible order reshuffling.

8. Multi-currency cost and close

The fab reports in AED while equipment may be USD, suppliers EUR, and assembly costs MYR. Each purchase, payroll line, sale, receipt, and transfer stores transaction rate, source, timestamp, realised FX, and revaluation status. Material, conversion, rework, scrap, depreciation, utilities, freight, and quality costs remain distinct.

Close reconciles purchase lots to receipts, receipts to inventory, lots to process steps, yield to inventory, tools to maintenance, utilities to invoices, finished lots to sales, customer claims, supplier certificates, intercompany assembly, tax, FX, and GL. Cost roll-up stores standard, actual, variance, and approved override.

KPI	Before OSERP discipline	After OSERP discipline	Improvement
Lot genealogy completeness	94.3%	99.9%	+5.6 points
Yield investigation cycle	10 days	2 days	80% faster
Tool preventive compliance	81%	97%	+16 points
Chemical expiry loss	3.8%	0.9%	76% lower
Cost-rollup close	13 days	4 days	69% faster

Practice challenge

Create a device revision and recipe, receive a wafer lot with inspection, launch a work order, record an out-of-tolerance step, place a hold, rework and test, issue a critical spare, calculate yield, reserve released devices, ship a customer lot in USD, process a quality claim, revalue EUR material, and close the fab period. Explain every field, status, formula, permission, journal, tax result, API identifier, exception, and audit event.

Related: Inventory field guide, Purchase Order field guide, Sales Order field guide, Fixed Asset field guide, and API cookbook.