Ceramic four-sided lead flat package tube (CQFP)

CQFP (CERAMIC QUAD FLAT PACKAGE) is a four-sided lead flat package using ceramic substrates (AL₂O₃ or ALN), leading in high reliability electronics

• Core advantages of CQFP packaging

1. High density interconnection capability

Multi-pin design: the number of pins can reach 64256+, support complex IC packaging (FPGA, ASIC), and the pin spacing can be as low as 0.5MM.

Four sides lead to the structure: it saves more than 70% PCB area compared with DIP/CDIP, which is suitable for high integration scenarios.

2. Excellent electrical properties

Low parasitic parameters: short pin design reduces inductance (<1NH) and capacitance, supporting high speed signals (>1GHZ).

Insulation of ceramic substrate: volume resistivity>10¹⁴ Ω·CM, dielectric constant 910 (1MHZ), suitable for high frequency mixed signal circuits.

3. Thermal management and reliability

High thermal conductivity ceramic: ALN substrate thermal conductivity 150200 W/M·K, can be integrated with metal heat sink (CUMO alloy).

Air-tight packaging: glass/metal seal, leakage rate <1×10⁻⁸ ATM·CC³/SEC, MILSTD883 certified.

4. Environmental adaptability

Wide temperature working: 55°C to +200°C, resistant to humidity and heat, salt spray corrosion, suitable for military industry, aerospace.

• Prominent technical indicators in industrial applications

| qualification         | Typical values/characteristics                    | Application impact

| Pin count / spacing | 64256 pins, spacing 0.51.27MM | High complexity IC packaging (SOC, FPGA)

| Thermal resistance (RTH) | 515°C/W (depending on substrate material and heat dissipation design) | Supports stable operation of 1530W power devices

| frequency response         | DC~10GHZ+                       | High-speed data converter, RF front end module

| Air tightness grade | Helium leak rate <1×10⁻⁸ ATM·CC³/SEC | Long life guarantee for aerospace and deep sea equipment

| mechanical strength         | Bending strength> 200MPA                 | Vehicle-mounted electronic vibration resistance requirements (EV electronic control system)

Signal integrity | The transmission rate can reach more than 10 GBPS          | Insertion loss <0.5 DB @ 10 GHZ

| Thermal cycle capacity |65°C to +150°C                     |No failure in 500 cycles

| temperature             | Military standard 55°C to +175°C                | Civilian grade 40°C to +125°C

Compare other packaging types:

Plastic QFP (PQFP): low cost but poor temperature resistance (40°C~125°C), insufficient gas tightness.

BGA: Higher density but difficult to repair, thermal cycle reliability is lower than ceramic packaging.

• The most suitable application scenarios

CQFP is mainly used in the following high reliability fields:

1. Aerospace and defense

Satellite payload electronics: radiation resistant packaging for onboard computers and attitude control IC.

Radar signal processing: ADC/DAC chip packaging for X-band radar.

2. High-end industry and energy

Power electronics: high temperature resistant packaging for IGBT drive and high voltage isolation devices.

Oil exploration equipment: high pressure and vibration resistant packaging of downhole sensors.

3. Communications infrastructure

5G base station: high frequency packaging of millimeter wave RF front end module (GAN PA).

Optical communication DSP: signal processing IC for 400G/800G coherent optical modules.

4. Automotive electronics (high reliability segment)

Autonomous driving ECU: multi-core processor stable operation in high temperature environment.

On-board radar: MMIC packaging for 77GHZ millimeter wave radar.

• Future development trend

1. High frequency and heterogeneous integration

Low temperature co-fired ceramics (LTCC): integrated passive components that support 20GHZ+mm wave applications.

2.5D/3D packaging: multi-chip integration through silicon interposer to improve bandwidth (HBM memory stack).

2. Upgrade of heat dissipation technology

Embedded microchannel cooling: direct liquid cooling technology solves the heat flux density of>50W/CM².

Diamond substrate: local deposition of diamond, local thermal conductivity>2000 W/M·K.

3. Cost optimization and standardization

Panel-level packaging: large size ceramic substrate (300x300MM²) to reduce the cost of large-scale production.

Pin material substitution: Copper alloy instead of Kovar (KOVAR) reduces the material cost by 30%.

4. Expansion of emerging areas

Quantum computing: cryogenic packaging of superconducting qubit control circuits (below 4K).

Space economy: Inclusive demand for high reliability packaging of low-cost small satellites (CUBESAT).

CQFP packaging, with its high density, high reliability, and excellent thermal performance, holds an irreplaceable position in advanced fields such as aerospace, military, and communications. In the future, with the development of high-frequency communication, heterogeneous integration, and advanced cooling technologies, its applications will extend to cutting-edge areas like quantum technology and space commercialization. Through innovations in materials and processes, it will gradually reduce costs and penetrate high-value-added markets such as automotive electronics and energy.