As SiP packages contain two or more chips stacked vertically as well as horizontally, micro-vias with typical diameters ranging from approximately 200 to just a few microns are used to provide vertical electrical connections among them. These micro-vias may be present either in an interposer (which is also referred to as an IC substrate) layer or within the chips themselves. Formation of micro-vias is commonly accomplished through chemical etching, but this process has limitations. Although chemical etching is a proven methodology for silicon and glass, etching cannot be used with ceramics or organic materials. Additionally, the waste management required for chemical etching processes presents extra complications and costs.
Cutting various materials as part of the SiP manufacturing process is also a very delicate process. Whether cutting an interposer, depaneling a package substrate or scribing and dicing a silicon die, the size of the cuts can be extremely small and must be made with the highest precision and minimal surrounding damage. As chip designs become even more advanced and miniaturized with higher densities, the type of cuts required will also become more complex.
Furthermore, as the materials become thinner, contact-based mechanical methods could cause damage such as cracks and tears, so therefore, a non-contact laser process will improve yields and throughput.
The assorted types of materials which SiP packages comprise—for example, ceramics, organic laminate and glass—respond differently to different manufacturing processes. To further complicate matters, some materials are inhomogeneous, such as ABF and FR4, which contains glass fibers and epoxy resin, and some laminates, which are embedded with copper traces. Traditional manufacturing processes including mechanical saws and etching may work well with some materials but not as well with others. The same is also true with laser manufacturing processes, as not all lasers are the same. Furthermore, tradeoffs in areas including speed, precision, surrounding damage and cost are always present when comparing manufacturing processes.
MKS has a deep understanding of the challenges faced in designing and building SiP manufacturing systems. We’ve turned this knowledge into unique product features that provide an advantage when used in SiP manufacturing.
Challenges in SiP Manufacturing |
MKS Solutions |
Maximizing throughput & yield |
Pulsed lasers for high speed, yield and precision micromachining
Fast, high power laser measurement and profiling
High power/high fluence optics to manage the lasers
High speed and precision motorized positioners |
Improving SiP quality and reliability |
Nanosecond and picosecond lasers for highest quality micromachining
Robust, stable optical mounts |
Scaling the manufacturing process |
Applications engineering expertise & full range of products |
- 50+ years and thousands of alignment systems for optical applications
- Long-term partner to semiconductor manufacturing companies
- Full range of products: lasers, optics, motion, opto-mechanics, beam analysis
- Custom capabilities
- Product availability
- Ability to scale with you
- Global corporation and presence

Lasers |

Beam Analysis |

Motion Control |

Opto-Mechanics |
- Nanosecond and picosecond lasers
- DPSS Q-switched lasers
- High power hybrid fiber lasers
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- High power laser thermal sensors
- High power beam profilers
- Laser power/energy meters
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- Full range of motorized stages
- Motion controllers
- Manual Positioners
- Custom assemblies
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- Mirror mounts
- Lens positioners
- Integrated optical, opto-mechanical and electronic subassemblies
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One of the challenges for laser materials processing—including cutting and drilling—is removing only the desired material, usually through localized heating, while at the same time minimizing the extent of the heat-affected zone (HAZ) to any of the remaining material. Delivering laser irradiation with near perfect beam quality precisely to the target region is a necessary step to achieving this desired result. Shorter wavelengths and, in particular, shorter pulse widths are advantageous to achieving higher-quality results.
For singulation of SiP devices, lasers in the ns pulse width regime at UV and green wavelengths, such as the Spectra Physics® Talon laser, may be suitable. However, challenges arise if excess heating cannot be tolerated, especially as these devices become further condensed and more densely packed. This leads to an interest in laser processing with even shorter pulse durations for reduced HAZ. Such may be the case if there are encapsulations that use a heat-sensitive bonding media, such as solder or adhesive, which may fail under excess thermal loading. Moreover, the presence of copper traces embedded within the SiP laminate, which can become excessively hot and result in the potential for layer delamination, can create additional difficulties.
To meet these challenges and to enable the advancement of SiP technology, ultrashort pulse (USP) lasers, like the Spectra Physics IceFyre® laser, can be employed. Ultrashort pulse widths in the ps and fs regime yield intense peak powers that result in nonlinear absorption at the sample for instantaneous material vaporization, very minimal heat transfer into the material, and a negligible HAZ. The result is a fast, high precision, high-quality cut or drill which leads to higher throughput and fewer part failures.