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TECHNOLOGY TRENDS

Pressure clip sintering for high-power electronics

By Eric Kuah [ASM Pacific Technology Ltd]

T h e fo c u s o n ve h i cl e a method whereby the semiconductor chip they improve the thermal conductivity

is attached to a substrate using a silver
electrifications and clean
pathway, thereby averting overheating in the
emissions has garnered much
attention and press coverage. or copper paste as the main elemental package by avoiding the formation of hot
spots. Copper clips, therefore, improve the
component. For the chip to connect to the
In light of this attention, major vehicle other connecting point to generate high electrical performance by reducing parasitic
companies in the US, Europe, Japan, China, voltage and deliver high current, a clip is inductance. Parasitic inductance is an
and South Korea have announced their an alternative interconnect to heavy wedge unwanted inductance effect that is present in
intentions of building modules for battery aluminum wire bonding. We will discuss electronic modules that prevents electrical
electric vehicles (BEV) or plug-in hybrid the motivations of using a clip interconnect current flowing through electrical circuitry.
electric vehicles (PHEV). This global scheme for HPE and its part in the assembly It should be noted that inductance is only
demand further drives the market valuation journey while exploring the positives of welcome when it is deliberately created
– previously valued at $163.01 billion in pressure clip sintering. using an inductor, along with a function in
2020 – it is projected to hit $823.75 billion mind. The reduction of parasitic induction,
by 2030—a cumulative average growth rate Motivation for using clip therefore, will translate into improvement
(CAGR) of 18.2% from 2021 to 2030 [1]. interconnection in HPE for the HPE package reliability when a clip
As BEV and/or PHEV products continue A clip interconnection used for HPE interconnect is employed.
to grow in demand, one thing that remains usually has copper as the base material Another consideration for clip sintering in
constant is their requirement for high- because of its high thermal conductivity. HPE is to account for built-up stress between
power electronics (HPE). This class of HPE Copper clips are used to replace heavy the interface of the semiconductor die and
package will then require pressure sintering, wedge aluminum interconnect because the metallic clip. The resulting stress tensor

Figure 1: Clip designs in HPE for stress relief.

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