New technology for high aspect ratio microstructures in glass – Interview with LPKF Laser & Electronics

Over the last several years the laser industry has found new opportunities and garnered significant interest from the semiconductor field for manufacturing with glass substrates. Lasers are considered to be more cost-effective than non-laser-based technologies for a variety of semiconductor applications.

i-Micronews invites you to discover LPKF Laser & Electronics’s perspective in this interview with Dr.-Ing. Roman Ostholt, Managing Director Electronics. In this discussion, Yole Développement’s (Yole) analyst would like to introduce you to LPKF’s new laser technology dedicated to glass material, branded Vitrion.

As discussed during the interview, microsystems manufacturing can benefit from Vitrion’s LIDE technologies. One of the biggest applications is microfluidics, where tiny and precise device cavities and micro-holes must be made economically. Yole Développement has recently released a dedicated report on this industry entitled “Status of the Microfluidics Industry 2019”. It describes the market, the supply and value chains and the end-application requirements.

This interview has been conducted by Amandine Pizzagalli, Market & Technology Analyst at Yole.

Amandine Pizzagalli: Can you briefly introduce LPKF, its history and current activity?

Dr.-Ing. Roman Ostholt: LPKF Laser & Electronics AG is a technology company located in Garbsen, near Hannover in Germany. In its more than 40-year history, LPKF has earned an exceptional reputation as an innovator in various industries. Today we make use of laser technology in most of our products. In our established business segments, we serve the following four areas: scientific prototyping, laser plastic welding, thin film photovoltaics and electronic production. In addition, we now also offer our LIDE technology, which addresses the microsystems technology market.

AP: Can you please say more about the relationship between LPKF and Vitrion? Where is Vitrion located? What is it and what is its business model?

RO: LPKF provides unique solutions that are geared to the needs of research and industry. The business model usually associated with LPKF is the sale of machinery. In the case of the LIDE technology, we have undertaken tremendously fast development. During the course of this development, we  became convinced that we are dealing with a truly disruptive technology for microsystems. We asked ourselves how we could quickly make our  technology and our accumulated  knowledge available to a wide range of customers across the different microsystems sectors. We then came to the conclusion that we have to change our primary business model and offer LIDE technology as a foundry service.

Today, LPKF offers this specialized manufacturing service under the Vitrion brand. The Vitrion team is located in our headquarters in Garbsen.

AP: How did you come up with the idea to create Vitrion?

RO: The change in our primary business model under the LPKF brand would have required a great deal of explanation, so we delibarately reinvented ourselves and created a new brand: Vitrion.

AP: What specific technology has Vitrion developed?

RO: We developed a technology called “Laser Induced Deep Etching” or just LIDE. LIDE is a two-step process to manufacture particularly deep microfeatures in glass with unprecedented quality and precision. A significant advantage of the LIDE technology is the incredible high processing speed and efficiency, which translate into economic benefits. For example, we can produce up to 5,000 micro-modifications per second with high precision and of course without any kind of surface defects.

AP: Can you plan tell us which main market segments and applications Vitrion supports?

RO: LIDE can be used to produce micro-holes, microcuts as well as open and closed cavities. With this versatility, we see a wide range of applications in MEMS and integrated circuit packaging, applications in which glass has always been of great interest, but where it is used only to a small extent due to its limited processing possibilities. Apart from that, we are looking at opportunities in microfluidics and life science applications where LIDE enables freedom to design flow-through features, for example, something which has not been possible to do, or not at that low cost level.

AP: What value does Vitrion’s LIDE technology add? What are the competitive advantages of your products for the semiconductor industry?

RO: Glass is an amorphous material and therefore there is inherently no possibility to etch it anisotropically. Deep structures with an aspect ratio greater than one, or with steep side walls, cannot be manufactured by wet chemical means. Other technologies also lack quality. LIDE tackles exactly these points. It enables the economical production of high quality microstructures in glass with aspect ratios of up to 1:50. As a direct write technology, we can adapt layout changes within minutes and help to shorten the development cycles. But also after the R&D evaluation phase, we can also offer an attractive price level in series production. In other words, we offer rapid prototyping and rapid manufacturing at the same time.

AP: Is there a technology point where your technology could be used instead of alternative solutions for semiconductor applications?

RO: Absolutely, wherever developers resort to established semiconductor materials as a basic material like carbonate just because there are manufacturing processes for deep microstructures such as Deep Reactive Ion Etching (DRIE) should think twice. We probably have a more cost-efficient and better solution to offer. In addition, glass offers a unique property profile that can be used advantageously depending on the application.

AP: What wafers sizes can you process? Can you process panel substrate size?

RO: We have the capability to work with all wafer formats and glass panels of up to 510 mm x 510 mm. Anyhow, we would like to encourage every customer who is interested in panel formats to work with square panels with a side length of 150 mm or 300 mm.

AP: What features size can you achieve in terms of aspect ratio ?

RO: A typical aspect ratio of LIDE manufactured micro features is 1:10 but it can be as high as 1:50. The smallest feature size made by LIDE is 10 µm.

AP: Is your technology able to process any type of glass such as borosilicate and fused silica?

RO: Yes, we can adapt the processing parameters according to the type of glass, but we can work with all silicate based glasses. Furthermore we are non-captive and are open to work with every glass supplier.

AP: What do you see as the next applications driving glass material use in the semiconductor field?

RO: Glass is already used in a multitude of applications. In the fields of display and microfluidics, it is hard to imagine designing and manufacturing without glass. In electronics packaging, however, it is not yet used to the extent that would be indicated by the fundamental material properties.

We are convinced that with LIDE we can make a significant contribution to the further spread of glass in packaging, irrespective of whether as a capping wafer, spacer wafer, interposer or glass embedded fan-out package.

AP: How do you foresee the evolution of laser technology market landscape in coming years?

RO: I think the era of low-hanging fruits has come to an end in laser technology. Due to the already widespread use of laser-based processes in almost all areas of industry, truly new solutions are characterized by increasing complexity and significantly longer development cycles. In addition to that, we have seen a trend towards consolidation and vertical integration in the recent past.

Even more than today,  the future will see  large, vertically-integrated laser companies together with highly specialized companies with very specific expertise in certain laser processes. We will continue to consistently pursue our path of innovation.

AP: What will be the major evolution of the laser business for semiconductor manufacturing in the coming years?

RO: Discussing the end of Moore’s Law, Electronic Packaging is coming increasingly to the attention of the semiconductor industry. This means that structure sizes will continue to shrink and accuracy requirements will further increase. This is a big challenge for the way laser machines are usually designed today.  

AP: What are the next steps for Vitrion’s growth?

RO: On the basis of various customer requests we are gathering, we are working on adding upstream and downstream processes to our Vitrion offer. But, like our customers, we are absolutely technology agnostic in that respect.

About the interviewee

Roman Ostholt studied mechanical engineering at RWTH Aachen University and graduated in 2007 as Dipl.-Ing. He started his career as a research fellow at the Fraunhofer Institute of Laser Technology. After finishing his doctoral thesis in 2011, he joined LPKF Laser & Electronics AG as an Innovation Manager. In 2014 Roman Ostholt became Vice President Technology Management of LPKF and in that role, he was responsible for the development of LIDE technology. He is inventor and co-inventor of multiple patents in that field. Since 2018 he is in charge of LIDE business at LPKF Laser & Electronics AG  and became Managing Director of the Segment Electronics in September 2019 .

About the interviewer

Amandine Pizzagalli is a Technology & Market Analyst, Equipment & Materials – Semiconductor Manufacturing, at Yole Développement (Yole).
She is deeply involved in the development of the Semiconductor & Software division with the production of reports and custom consulting projects dedicated to the semiconductor equipment and materials industries and related manufacturing processes.
Amandine graduated from the engineering school, CPE Lyon (France), with a technical expertise in Semiconductor & Nano-Electronics and holds an electronics engineering degree followed by a master’s in semiconductor manufacturing technology from KTH Royal institute of technology (Sweden).

Related report

Status of the Microfluidics Industry 2019

Diversification of microfluidic technologies has led to burgeoning new applications and market growth, driving players’ interest and M&A.