MES + Automation + IT

Role in QLT Fabrication

A Manufacturing Execution System (MES) is the digital backbone of any semiconductor fabrication facility. For QLT's quantum photonic chip production, the MES orchestrates every wafer lot from incoming substrate through final test, enforcing process recipes, tracking yield in real time, and ensuring full traceability required for both quality control and ITAR compliance.

Without an MES, QLT would rely on paper travelers and manual data entry — acceptable for a handful of R&D wafers, but incompatible with the reproducibility and auditability required for product-grade quantum photonic processors. The MES integrates with every tool in the fab via SECS/GEM (SEMI E5/E37) protocols, creating a closed-loop manufacturing environment where recipe deviations, equipment faults, and yield excursions are detected automatically.

The MES + Automation infrastructure serves multiple functions in QLT's fabrication process:

• Recipe management ● centralized storage and version control of process recipes for ICP-RIE, PECVD, ALD, sputtering, and all other process tools; prevents unauthorized recipe modifications
• Lot tracking ● automated tracking of every wafer lot through 9 fabrication steps; barcode/RFID identification at each tool load/unload
• Yield analytics ● real-time statistical process control (SPC) with automatic out-of-control action plans (OCAP); tracks critical parameters like waveguide loss, film thickness uniformity, and etch depth
• Equipment integration ● SECS/GEM (SEMI E5/E37/E30) communication with all process tools; automated recipe download, run start/end logging, and alarm forwarding
• FOUP/carrier handling ● automated material handling system (AMHS) integration for wafer carrier tracking; interlocked to prevent wrong-lot loading
• Facility monitoring ● integration with building management system (BMS) for cleanroom particle counts, temperature/humidity, gas system status, and exhaust monitoring
• Compliance & traceability ● complete audit trail for ITAR/EAR compliance; electronic batch records; 21 CFR Part 11 electronic signatures (if needed for defense customers)

Why MES Matters for Quantum Photonics

Quantum photonic chip fabrication has tighter process windows than conventional semiconductor manufacturing. Waveguide propagation loss below 0.5 dB/m requires sub-nanometer control of sidewall roughness, and the Poovey switch air-gap tolerance is ±25 nm. An MES with integrated SPC catches drift in etch rates, deposition thicknesses, and lithography overlay before wafers are scrapped — critical when each MPW run costs $8–12k per die slot and takes 4–6 weeks.

Technical Specifications

MES Core Platform Requirements

SECS/GEM Equipment Integration

SEMI Equipment Communications Standard (SECS) and Generic Equipment Model (GEM) are the industry-standard protocols for semiconductor tool communication. Every process tool in the QLT fab must support SECS/GEM for MES integration.

SPC/APC Parameters for QLT Process

System Architecture

QLT MES + AUTOMATION SYSTEM ARCHITECTURE:

┌─────────────────────────────────────────────────────────────┐
│                    ENTERPRISE LAYER                          │
│  ERP (future) ← → MES Server ← → Engineering Data Server   │
│                         │                                    │
│              ┌──────────┼──────────┐                        │
│              ▼          ▼          ▼                         │
│         Dashboard    Reports    Alarms                       │
│         (Web UI)    (PDF/CSV)  (SMS/Email)                   │
├─────────────────────────────────────────────────────────────┤
│                    MES APPLICATION LAYER                     │
│                                                              │
│  ┌──────────┐ ┌──────────┐ ┌──────────┐ ┌──────────┐       │
│  │  Recipe   │ │   Lot    │ │   SPC    │ │  Yield   │       │
│  │ Manager   │ │ Tracker  │ │  Engine  │ │ Analytics│       │
│  └──────────┘ └──────────┘ └──────────┘ └──────────┘       │
│  ┌──────────┐ ┌──────────┐ ┌──────────┐ ┌──────────┐       │
│  │  APC /   │ │ Equipment│ │  Alarm   │ │  Audit   │       │
│  │   R2R    │ │  Monitor │ │  Manager │ │   Trail  │       │
│  └──────────┘ └──────────┘ └──────────┘ └──────────┘       │
├─────────────────────────────────────────────────────────────┤
│                 EQUIPMENT INTEGRATION LAYER                   │
│                                                              │
│  ┌──────────────────────────────────────────────────┐       │
│  │          SECS/GEM Gateway (Cimetrix/INFICON)      │       │
│  │   SEMI E5 │ E30 │ E37 │ E40 │ E87 │ E90 │ E116  │       │
│  └──────────────────────────────────────────────────┘       │
│         │          │          │          │                    │
│    ┌────┴───┐ ┌────┴───┐ ┌────┴───┐ ┌────┴───┐             │
│    │ICP-RIE │ │ PECVD  │ │  ALD   │ │Sputter │  ...        │
│    │Oxford  │ │Trion/Ox│ │Veeco/Ox│ │AJA/Kurt│             │
│    └────────┘ └────────┘ └────────┘ └────────┘             │
├─────────────────────────────────────────────────────────────┤
│                    FACILITY LAYER                            │
│  BMS ← → Particle counters, Temp/RH, Gas monitors, Exhaust  │
│  SCADA ← → Power, UPS, Chiller, Vacuum pumps, N₂ supply     │
└─────────────────────────────────────────────────────────────┘

Lot Tracking Workflow

QLT LOT LIFECYCLE ● MES-Managed:

LOT CREATION:
├── Operator scans incoming substrate barcode
├── MES creates lot record: lot ID, wafer count, substrate type
├── Assigns process route (9-step flow)
└── Generates electronic traveler (replaces paper)

AT EACH PROCESS STEP:
├── Operator scans lot barcode at tool load port
├── MES verifies: correct tool, correct step sequence, lot not on hold
├── MES downloads recipe to tool via SECS/GEM (S7F23 / S7F25)
├── Tool reports run start (S6F11 collection event)
├── Tool streams process data during run (S6F1 trace data)
├── Tool reports run end + result data (S6F11 collection event)
├── MES records: start time, end time, recipe, operator, all parameters
├── SPC engine evaluates parameters against control limits
│   ├── IN CONTROL → lot advances to next step
│   ├── OUT OF CONTROL → lot placed on HOLD; OCAP triggered
│   └── WARNING → lot flagged; engineering review notification
└── Lot status updated in WIP tracker

LOT COMPLETION:
├── Final test data recorded (optical + electrical)
├── Die yield calculated; yield map generated
├── Lot disposition: PASS → ship / FAIL → scrap or rework
└── Complete history archived (minimum 10 years for ITAR)

Run-to-Run (R2R) Advanced Process Control

APC uses feed-forward and feed-back control loops to compensate for process drift. For example, if ellipsometry after PECVD shows the SiO₂ film is 2% thin, the R2R controller adjusts the next wafer's deposition time to compensate — maintaining tighter thickness control than fixed recipes alone.

Vendor Options & Pricing

Enterprise MES Platforms

QLT Phased Deployment Recommendation

IT Infrastructure Pricing

Facility Requirements

Network Architecture

QLT FAB NETWORK TOPOLOGY:

INTERNET ←→ FIREWALL ←→ DMZ
                │
           CORE SWITCH (Cisco 9300)
          ┌─────┼─────────────┐
          ▼     ▼             ▼
     VLAN 10  VLAN 20      VLAN 30
     OFFICE   MES/IT       FAB TOOLS
       │        │              │
    Desktops  MES Server    ┌──┴──────────────┐
    Wi-Fi     DB Server     │ SECS/GEM Gateway │
    Printers  NAS Backup    │   (Cimetrix)     │
              UPS Mgmt      └──┬──────────────┘
                               │
                    ┌──────────┼──────────┐
                    ▼          ▼          ▼
               ICP-RIE      PECVD       ALD
               (E5/E37)    (E5/E37)   (E5/E37)    ...

SECURITY:
├── VLAN 30 (fab tools) → NO internet access; air-gapped from office
├── VLAN 20 (MES) → restricted internet (updates only via approved proxy)
├── VLAN 10 (office) → standard internet with content filtering
├── Inter-VLAN routing: MES ↔ Fab only; Office → MES (read-only dashboards)
└── VPN (WireGuard) for remote engineering access with MFA

Safety & Handling

Data Security & Compliance

Operational Risks