Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Semiconductor lead frame surface treatment method

A lead frame and surface treatment technology, which is applied in the field of surface treatment of semiconductor lead frames, can solve the problems of loose welding of diaphragm layers and poor welding quality, and achieve excellent solderability, good solderability, and avoid oxidation.

Active Publication Date: 2015-09-09
SICHUAN JINWAN ELECTRONICS
View PDF4 Cites 12 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0005] In order to overcome the defects of loose welding and poor welding quality caused by the formed diaphragm layer during welding of the existing lead frame, the invention provides a surface treatment process of the lead frame, which is provided with a layer of organic protection on the copper surface layer. layer to replace the diaphragm layer, and when dipping tin and welding aluminum wire, this protective layer is naturally eliminated to achieve protection without affecting the welding effect

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0036] The present embodiment comprises the following process steps:

[0037] A. Ultrasonic degreasing: guide the power semiconductor lead frame into the ultrasonic degreasing agent for ultrasonic degreasing, and use sound wave vibration to loosen and fall off the oil stains on the surface, so as to remove the residual grease on the surface of the substrate during stamping. The temperature of the ultrasonic degreasing agent is 50°C (Celsius), the solubility of the ultrasonic degreasing agent is 50g / L (grams per liter), and the ultrasonic degreasing time is 10S (seconds).

[0038] B. Perform electrolytic degreasing: introduce the power semiconductor lead frame into the electrolytic degreasing agent for electrolytic degreasing, and use the hydrogen gas on the surface during electrolysis to remove the oil stains on the surface, so as to remove the residual grease on the surface of the substrate during stamping. The temperature is 55°C, the concentration of the electrolytic degrea...

Embodiment 2

[0046] A. Ultrasonic degreasing: guide the power semiconductor lead frame into the ultrasonic degreasing agent for ultrasonic degreasing, and use sound wave vibration to loosen and fall off the oil stains on the surface, so as to remove the residual grease on the surface of the substrate during stamping. The temperature of the ultrasonic degreasing agent is 55°C (Celsius), the solubility of the ultrasonic degreasing agent is 55g / L (grams per liter), and the ultrasonic degreasing time is 15S (seconds).

[0047] B. Perform electrolytic degreasing: introduce the power semiconductor lead frame into the electrolytic degreasing agent for electrolytic degreasing, and use the hydrogen gas on the surface during electrolysis to remove the oil stains on the surface, so as to remove the residual grease on the surface of the substrate during stamping. The temperature is 50°C, the concentration of the electrolytic degreaser is 55g / L, and the time is 16S.

[0048] C. Sulfuric aci...

Embodiment 3

[0055] A. Ultrasonic degreasing: guide the power semiconductor lead frame into the ultrasonic degreasing agent for ultrasonic degreasing, and use sound wave vibration to loosen and fall off the oil stains on the surface, so as to remove the residual grease on the surface of the substrate during stamping. The temperature of the ultrasonic degreasing agent is 60°C (Celsius), the solubility of the ultrasonic degreasing agent is 60g / L (grams per liter), and the ultrasonic degreasing time is 20S (seconds).

[0056] B. Perform electrolytic degreasing: introduce the power semiconductor lead frame into the electrolytic degreasing agent for electrolytic degreasing, and use the hydrogen gas on the surface during electrolysis to remove the oil stains on the surface, so as to remove the residual grease on the surface of the substrate during stamping. The temperature is 55°C, the concentration of the electrolytic degreaser is 58g / L, and the time is 16S.

[0057] C. Sulfuric aci...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

The invention discloses a semiconductor lead frame surface treatment method sequentially comprising ultrasonic degreasing, electrolytic degreasing, washing, sulfuric acid neutralization and activation, washing, electro-coppering, washing, acid neutralization, washing, copper protection, washing, hot washing, and drying. The step of copper protection has the following specific technical requirements: a semiconductor lead frame is guided into and immersed in protection liquid to achieve the purpose of making the semiconductor lead frame coated with a copper protective film, wherein the pH of the protection liquid is 5-7, the temperature is 20-40 DEG C, the immersion time is 10-20S, and the protection liquid contains 9-15g / L alkyl benzimidazole and 1-3g / L acetic acid. An organic protective layer is arranged on a copper surface layer to replace a diaphragm layer, and the protective layer is naturally removed during tin dipping and aluminum wire welding. Thus, protection is achieved without affecting the welding effect.

Description

technical field [0001] The invention relates to a method for manufacturing a semiconductor lead frame, in particular to a surface treatment method for a semiconductor lead frame. Background technique [0002] A very important material in semiconductor packaging is the lead frame. Lead frame is one of the three basic raw materials for semiconductor packaging (the other two are plastic packaging materials and the chip itself). The internal interconnection in the semiconductor package usually uses gold wire, aluminum wire, and copper wire to realize the connection between the pin and the chip. Gold wire ball thermosonic pressure welding using gold wire is mostly used for internal interconnection of memories, processors, and ASIC chips. Cold ultrasonic pressure welding using aluminum wire is mostly used for the packaging of semiconductor devices such as power and rectifiers. [0003] The lead frame is generally made of copper alloy as the base material. The manufacturing proc...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
IPC IPC(8): H01L21/48C25D7/12C25D3/38C25D5/34C25D5/48C23C28/00
CPCC23C28/00C25D3/38C25D5/34C25D5/48C25D7/12H01L21/4821
Inventor 王锋涛李南生黄斌夏超华
Owner SICHUAN JINWAN ELECTRONICS
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com