CONTRACT MANUFACTURING Figure 2: Laserssel LSR
solder bump and 30 micron chip soldering, and uses shorter TAL compared to mass reflow. Also, cooling speed is directly related to the formation of multigrain as well as uniform, thin formation of intermetallic compounds, resulting in better shear strength.
Recently LSR is adopted to high-end GPU mass production process for top-tier consumer product manufacturer for its stable production capability to eliminate warpage and provide better solderability. BSOM is Laserssel’s patented, core technology. LSR uses BSOM to transform spot beams to area beams, significantly reducing substrate warpage by heating small selected areas and leaving the rest of the area unheated. This protects other areas of the PCB from damage. Additionally, area laser selective reflow does not create hot spots (high-energy density), which often is the key problematic issue with spot laser reflow systems. Area laser selective reflow also increases productivity and minimises warpage and thermal damage. An additional advantage to heating only a selected laser region is that when the area laser is applied to chips, only those chips are being heated to targeted reflow temperature. Regions immediately outside of the laser beam area show dramatically lower temperature on the infrared camera image (Figure 3).
Laserssel’s LSR technology has been designed into five innovative series: LSR Series: LSR1000 – with a bonding accuracy of greater than ±5.0 micron and a single-laser head of 1kW, a variable beam size range of 5-50mm and/or 15-75mm, fixed beam of as large as 100x100mm, and a rectangular and square beam shape. Also, it uses IR camera and beam profiler monitoring and features a footprint of 1.7x1.8m, weighing in at 2,500kg. LCB Series: LCB3000 – This series also
features bonding accuracy of greater than ±5.0 micron, but with a single-laser head of 3kW. Beam size ranges from 15-75mm or larger. It features a square beam shape, IR wavelength and monitoring via IR camera, beam profiler and real-time power meter. The LCB series’ footprint is 1.8x1.8 m and weighs 3,000kg.
pLSR Series uses a 100W laser and IR wavelength to bond cantilever on probe card. It has vision monitoring with a footprint of 2.3x2m and weighs 2,500kg.
rLSR Series uses a 400W laser to rework any type of chip, passive components and micro-sized LED. This series’ footprint is 2x2.5m and weighs 2,500kg.
The company’s products reach a range of markets because of the functionality and performance they bring to smaller/thinner devices. These markets include mini/micro LED display, semiconductor, mobile/ wearable, and electric vehicle (EV). • Mini/Micro LED Display: Mini LED Backlight Unit (BLU) has become a good alternative to
OLED display in recent mid- to large-size display. OLED had been dominating display in the mobile and television industries with 1,000,000:1 contrast ratio, superior to LCD, but also experienced downfalls with burn-in issues and high cost. In 2021, Mini LED used as an LCB BLU emerged as a strong competitor of OLED, offering extensive improvement on both burn-in and cost. Mini LED BLU is an array of tens of thousands of tiny LEDs as small as 100 micron and each LED needs to be reflowed and reworked by LSR for the best quality in bonding strength, warpage and surface damage. • Semiconductor: Most advanced semiconductor products such as AI, GPU, CPU and HBMs are facing challenges today from diverse directions. Thin die and substrates make it more difficult to build packages without warpage. Interposer packaging, multi-stacked packages and very fine-pitch solder bumps tend to create different types of issues with conventional reflow ovens. Accurately controlled area lasers have been proven to solve these problems.
• Mobile and Wearable: IoT has brought various forms of electric device substrates to light such as fabric, 3D polymer, bendable display, and heat-sensitive and warpage-prone substrates. However, these new substrates can create issues with the reflow process due to their heat-sensitive characteristics. By heating up only small selected areas with area laser beam for a few seconds, LSR turns various kinds of materials into ready-to-be-used substrates. • EV: EV uses various types of heat-sensitive substrates where thermal monitor and control is critical. However, such heat- sensitive substrates cannot be reflowed with conventional reflow due to the very low temperature specification. With its aimed soldering and area laser, LSR enables the automation of soldering components to these heat-sensitive substrates.
Laserssel Co., Ltd.
www.laserssel.com
Figure 3: Laserssel BSOM IR Camera Image JULY/AUGUST 2021 | ELECTRONICS TODAY 39
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54
