-
- News
- Books
Featured Books
- design007 Magazine
Latest Issues
Current IssueSilicon to Systems: From Soup to Nuts
This month, we asked our expert contributors to weigh in on silicon to systems—what it means to PCB designers and design engineers, EDA companies, and the rest of the PCB supply chain... from soup to nuts.
Cost Drivers
In this month’s issue of Design007 Magazine, our expert contributors explain the impact of cost drivers on PCB designs and the need to consider a design budget. They discuss the myriad design cycle cost adders—hidden and not so hidden—and ways to add value.
Mechatronics
Our expert contributors discuss the advent of mechatronics in PCB design, the challenges and opportunities this creates for circuit board designers, and the benefits—to the employee and the company—of becoming a mechatronics engineer.
- Articles
- Columns
Search Console
- Links
- Events
||| MENU - design007 Magazine
Book Excerpt: The Printed Circuit Assembler’s Guide to... Low-Temperature Soldering, Vol. 2
June 18, 2024 | I-Connect007 Editorial TeamEstimated reading time: 1 minute
The Printed Circuit Assembler’s Guide to... Low-Temperature Soldering, Vol. 2, by Morgana Ribas, et al, MacDermid Alpha Electronics Solutions
Chapter 1: Introduction to Low-temperature Soldering
Low-temperature solders (LTS) continue to attract serious interest from the electronics industry. These solder alloys enable the use of lower glass transition temperature (Tg) substrates and components due to the lower processing temperature, promote long-term reliability by reducing exposure to thermal excursion, and enable organizations to meet sustainability targets. Perhaps more significantly, low-temperature soldering is an enabling technology that mitigates warpage-induced defects of the ultra-thin, high IO chip-scale packages used in complex electronic devices. Use of higher reflow temperature Sn-Ag-Cu (SAC) solders in package-on-package (PoP) bottom and PoP memory technology can potentially result in soldering defects such as non-wet opens, solder bridging, and head-in-pillow.
The eutectic 42Sn-58Bi alloy melts at 138°C and has been considered for SMT soldering since the transition from tin-lead to lead-free solders. This alloy is quite interesting as a solder, as bismuth is one of the few elements forming a solid solution in tin. Its binary composition, lamellar microstructure, and eutectic melting point resemble that of eutectic tin-lead. However, this first-generation LTS alloy lagged behind traditional lead-free alloys in solder joint thermomechanical and drop shock reliability and limited thermal cycling performance.
The transition to lead-free solders was motivated by regulatory compliance, and SAC305 (96.5% tin, 3% silver, 0.5% copper) was chosen as the best cost-benefit alternative. As the electronics industry evolved, so did solder joint reliability requirements. Several new solders were introduced to meet specific reliability requirements.
Suggested Items
Indium to Showcase Durafuse Solder Technology at Productronica India
09/02/2024 | Indium CorporationAs one of the leading materials providers to the electronics assembly industry, Indium Corporation® is proud to feature its innovative Durafuse® solder technology at Productronica India, September 11-13, in Delhi, India.
Indium to Highlight High-Reliability Solder Solutions at SMTA Guadalajara
08/28/2024 | Indium CorporationIndium Corporation® will feature a range of industry-leading, high-reliability solder products at the Guadalajara Expo & Tech Forum in Guadalajara, Jalisco, Mexico, September 11-12.
My Drop Shock Testing Experiments to Determine Reliability in PCBs
08/14/2024 | Palash Vyas, Ph.D, Graduate Research AssistantTablets, digital cameras, and smartphones are portable electronics that have become increasingly popular. Compact design and improved functionality are common product and package design trends. However, because they are portable, these devices may fall and cause internal damage. In addition, customers may use products in different environments, exposing them to risks that could cause harm. For example, a smart device such as a phone or tablet could be dropped while being used, or a warehouse shipment could be handled carelessly and fall. Products must have sufficient mechanical shock reliability to reduce the likelihood of damage.
Book Excerpt: The Printed Circuit Assembler’s Guide to... Factory Analytics, Chapter 3
08/14/2024 | I-Connect007 Editorial TeamChapter 3 of this book delves into the critical aspects of the SMT process, focusing on the reflow oven and automated optical inspection (AOI) machine. Highlighted are the key roles of the line operator, manufacturing engineer, and quality manager in maintaining efficient operations and high-quality PCBAs.
Indium Awards Silver Quill Honor to Authors of Cutting-Edge Technical Content
08/08/2024 | Indium CorporationIndium Corporation has honored nine of its employees for their technical industry contributions with its annual Silver Quill Award. While the company’s thought leaders present technical content at industry events throughout the year, Silver Quill provides special recognition to the most innovative and cutting-edge papers.