TO252 (DPAK) Power Semiconductor Packaging Line Solution

HYRNUS provides TO252 (DPAK) packaging equipment and production line solutions for MOSFETs, Schottky diodes, rectifiers, TVS devices, and other power semiconductor products.

Based on the die size, lead frame design, die attach material, wire bonding method, package structure, electrical test requirements, and target throughput, we can configure stand-alone machines, semi-automatic lines, or fully automated packaging and testing lines. The process scope can cover wafer back grinding, wafer dicing, die attach, wire bonding, molding, post-mold curing, trim and form, marking, final testing, sorting, and packing.

TO252, also known as DPAK, is a surface-mount package widely used for power semiconductor devices. Its compact body is compatible with SMT assembly, while the exposed metal tab and lead frame provide an efficient thermal path from the semiconductor die to the printed circuit board.

Compared with larger through-hole power packages, TO252 is better suited to automated assembly and space-efficient PCB design. It is commonly selected for high-volume applications in consumer electronics, automotive electronics, industrial power supplies, and new energy systems.

Key Benefits of the TO252 Package

Feature	Production and Product Benefit
SMT Compatibility	Supports automated placement and reflow assembly.
Compact Size	Reduces PCB space requirements and supports higher component density.
Good Thermal Performance	Provides an effective heat transfer path through the lead frame and mounting pad.
Cost Efficiency	Suitable for high-volume manufacturing with a relatively economical package structure.
High Automation Potential	Can be processed through continuous die attach, wire bonding, molding, forming, and test operations.
Application Reliability	Can be engineered for consumer, industrial, and automotive-grade power applications.

Typical Applications

Application Area	Typical Products
Consumer Electronics	PD fast chargers, adapters, and smart home power modules
Power Management	Switching power supplies, DC/DC converters, and LED drivers
Automotive Electronics	Battery management systems, ECUs, motor drives, and onboard power modules
Industrial Control	Industrial power supplies, control modules, and drive systems
New Energy	Energy storage systems and auxiliary power supplies for photovoltaic inverters
Power Equipment	UPS systems and other power conversion equipment

Main Components of a TO252 Device

1. Lead Frame

The lead frame is typically made from a copper alloy. It provides electrical connections, a thermal path, and mechanical support. Its dimensional accuracy, surface condition, plating quality, and die pad flatness influence die attach, wire bonding, molding, and final forming quality.

2. Semiconductor Die

The semiconductor die performs the switching, rectification, or power control function. Wafer thickness, dicing quality, die surface condition, and back-side metallization can affect die attach quality, thermal resistance, and long-term reliability.

3. Bond Wire

Bond wire creates the electrical connection between the die pads and the lead frame. Aluminum wire, heavy aluminum wire, ribbon, or another interconnection method may be selected according to current capacity, pad design, loop geometry, and reliability requirements.

4. Molding Compound

The molding compound provides electrical insulation, moisture resistance, and mechanical protection for the die and internal interconnections. Material selection and molding parameters must be coordinated to control voids, delamination, wire sweep, flash, and package stress.

Key Challenges in TO252 Packaging

1. Die Attach Quality and Thermal Performance

TO252 devices generate heat during operation. The interface between the semiconductor die and lead frame directly affects thermal resistance, electrical performance, and reliability. The process must control die position, tilt, bond-line thickness, void rate, adhesive coverage, solder wetting, and attach strength.

2. Stable Wire Bonding

Power devices require consistent current-carrying capability. The wire bonding process must accurately control bonding position, force, ultrasonic energy, bonding time, wire diameter, and loop geometry. Unstable parameters can cause weak bonds, pad damage, lifted wires, abnormal loops, or increased electrical resistance.

3. Molding Consistency

The molding process must protect the die and wire connections without creating wire sweep, incomplete fill, voids, delamination, excessive flash, or package cracking. The molding machine, mold design, molding compound, transfer conditions, and cure profile must be matched to the device structure.

4. Trim and Form Accuracy

As an SMT package, TO252 requires controlled lead geometry and coplanarity. Trim and form equipment must maintain lead dimensions while minimizing burrs, package stress, lead deformation, and body cracking.

5. Efficient Final Testing and Sorting

High-volume production requires not only accurate electrical testing, but also stable feeding, orientation, contact, binning, and data recording. The test handler must be selected according to the device type, test time, number of bins, temperature requirements, and target UPH.

6. Manufacturing Cost Control

Package cost has a direct effect on device competitiveness. Equipment utilization, line automation, changeover time, yield, consumable use, maintenance requirements, and overall equipment effectiveness should be considered during line planning.

Complete TO252 Packaging Process

1. Wafer Incoming Inspection

Incoming wafer inspection confirms the wafer model, dimensions, thickness, visual condition, wafer map, die layout, back-side condition, and process lot information before grinding and dicing.

Key Process Controls

Wafer identification and traceability
Initial wafer thickness and warpage
Die map and street layout
Surface and edge condition
Back-side metallization or coating status

2. Wafer Back Grinding

Wafer back grinding reduces the wafer to the target thickness required for package height, thermal performance, die strength, and downstream handling.

Key Process Controls

Final wafer thickness
Thickness uniformity
Wafer warpage
Surface roughness
Edge chipping
Post-grinding cleaning and handling

3. Wafer Dicing

The dicing saw separates the wafer into individual dies according to the cutting streets. Stable cutting quality is required so that each die matches the lead frame die pad and can be picked and placed reliably.

Key Process Controls

Cutting accuracy
Die dimension consistency
Chipping and crack control
Blade and spindle condition
Cutting surface cleanliness
Wafer map and die tracking

4. Die Attach

The die bonder places the semiconductor die onto the heat-spreading pad of the TO252 lead frame. Conductive epoxy, solder, eutectic bonding, or another qualified attachment method may be used according to the device design and thermal requirements.

Key Process Controls

Die position and rotation
Die tilt
Adhesive or solder volume
Bond-line thickness
Placement force
Heating and cure profile
Void rate and attach strength

Recommended equipment

Wafer Grinder

HY-WT3005 Fully Automatic Ultra-Precision Wafer Thinning Machine.
Dicing Saw

HY-WD1202 Wafer Singulation Dicing Saw.
Die Donder

HY-GD800 Fully Automatic Multi-Function Die Bonder. Typical placement accuracy can reach ±5 μm and ±0.1°, subject to the final product and process configuration.

5. Wire Bonding

Wire bonding creates the electrical connection between the die pads and lead frame. The bonding platform, capillary or wedge, wire material, wire diameter, ultrasonic system, and bonding program must be selected according to the device structure.

Key Process Controls

Bonding position
Bonding force
Ultrasonic energy
Bonding time
Wire diameter
Loop height and span
Pull strength and bond quality

6. Molding

Transfer molding encapsulates the die, bond wires, and part of the lead frame with an epoxy molding compound. The process provides insulation, moisture resistance, and mechanical protection.

Key Process Controls

Mold temperature
Transfer pressure and speed
Cavity filling
Wire sweep
Voids and incomplete fill
Flash and bleed
Delamination risk
Package stress

7. Post-Mold Cure

After molding, post-mold cure completes the cross-linking of the molding compound and stabilizes its mechanical, insulation, and moisture-resistance properties.

Key Process Controls

Cure temperature
Cure time
Loading method
Lot separation
Oven uniformity
Process traceability

8. Trim and Form

Trim and form equipment removes the lead frame tie bars and forms the leads to the required TO252 geometry for SMT mounting

Key Process Controls

Lead dimensions
Lead coplanarity
Forming angle
Burr control
Package body protection
Feeding and strip positioning stability

Recommended equipment

Wire Bonding Machine

HY-HW3850 Automatic Ultrasonic Heavy Aluminum Wire Wedge Bonder
Molding Mold

HY-PM252-6R Molding Mold
Food Processing & Catering

HY-TF210 Automatic Trim and Form System

9. Marking and Visual Inspection

The marking system applies product identification and traceability information to the package surface. A vision system can be integrated to verify mark position, content, clarity, and package appearance.

Key Process Controls

Product model
Batch or lot number
Date code
Manufacturer information
Traceability code
Character and appearance inspection

10. Final Test and Sorting

The final test handler feeds, positions, contacts, tests, and sorts finished devices according to the electrical test results.

Key Process Controls

Breakdown voltage
Leakage current
On-resistance
Threshold voltage
Forward voltage
Static electrical parameters
Customized device parameters
Bin classification and data recording

11. Packing

Qualified TO252 devices are packed according to customer handling and SMT assembly requirements. Packaging specifications should define orientation, quantity, labeling, moisture protection, and traceability.

Key Process Controls

Tape-and-reel packing
Tube or tray packing where applicable
Orientation control
Labeling and lot recording
Moisture-barrier packaging
Final outgoing inspection

Test Handle

HY-TS980 Turret Test Handler
Turret Sorter

HY-TH800 Turret-Style Integrated System

Recommended Equipment Configuration

Process	Recommended Configuration	Primary Function
Wafer Back Grinding	HY-WT3005	Automatic wafer thinning, thickness control, alignment, cleaning, and handling
Wafer Dicing	HY-WD1202	Wafer singulation with cutting accuracy and chipping control
Die Attach	HY-GD800	Die pickup, vision alignment, adhesive or solder process, and high-precision placement
Wire Bonding	HY-HW3850	Electrical interconnection between the die and lead frame
Molding	HY-PM252-6R	Transfer molding and package encapsulation
Post-Mold Cure	Curing Oven	Controlled post-mold curing and batch management
Trim and Form	HY-TF210	TO252 lead trimming and forming
Marking	Automatic Laser Marking System	Product identification and traceability marking
Final Test and Sorting	HY-TS980	Electrical testing, binning, and automatic device sorting
Packing	HY-TH800	Orientation control, counting, packing, and labeling

Flexible Production Line Configurations

Stand-Alone Equipment

Suitable for laboratories, process development, pilot production, or replacement and expansion of individual operations in an existing factory.

Semi-Automatic Line

Retains selected manual loading or transfer steps while using automatic positioning, processing, inspection, and data recording to improve consistency and reduce labor dependence.

Fully Automatic Line

Connects equipment through automatic feeding, material transfer, online inspection, sorting, and production data management to reduce handling between operations and support high-volume manufacturing.

Multi-Package Compatibility

Some machines can support TO252, TO220, or other related power packages by changing fixtures, tracks, molds, contact parts, tooling, and process programs. Compatibility must be evaluated against the actual package dimensions, lead frame structure, process parameters, and throughput requirements.

Request a Customized TO252 Packaging Solution

Send us your device drawing, lead frame information, process flow, target capacity, automation requirements, and factory conditions. HYRNUS will evaluate the project and recommend a suitable stand-alone machine configuration or complete TO252 packaging and testing line.

Contact Our Engineering Team

FAQs

Can the line be customized for different TO252 divices?

Yes. The configuration should be adjusted according to die size, lead frame design, die attach material, bonding method, molding structure, test program, input and output format, and target throughput.

Can individual machines be purchased separately?

Yes. Customers can select a single machine, several connected processes, or a complete packaging and testing line.

Can the equipment also support TO220 products?

Some equipment can support TO220 or related power packages after changing fixtures, molds, tracks, tooling, contact parts, or programs. The final compatibility must be confirmed from the product drawings and process requirements.

Dose HYRNUS provide installation and process support?

Support can include installation, commissioning, trial production, operator training, maintenance training, and ongoing technical assistance, depending on the agreed project scope.