💿 How to View US and Korean Materials, Parts, and Equipment Differently

When it comes to investing in AI semiconductors, most people first think of a set group of companies. These are large-cap stocks like NVIDIA, TSMC, ASML, SK hynix, and Samsung Electronics. They are undoubtedly at the center of AI infrastructure. The problem, however, is that the market is already well aware of this. The fact that a company is good is always different from the fact that it's a good investment opportunity.

So recently, I've been looking in a slightly different direction. This is the realm of process equipment, inspection equipment, test equipment, materials, components, and gas/chemical supply systems, which are essential as AI semiconductors are sold in greater quantities and manufactured with increasing complexity. These are the so-called "so-bu-jang" companies—materials, components, and equipment suppliers.

However, one should not view US and Korean equipment and materials stocks in the same way. US equipment and materials companies generally have a strong global customer base and an independent technological position in specific processes. For example, $ACLS in ion implantation equipment, $VECO in laser annealing, ion beam deposition, and compound semiconductor equipment, $ONTO in advanced packaging inspection and metrology, and $ENTG in filters, materials, and contamination control—each has a relatively clear domain. Their customers are also often not solely dependent on specific Korean memory companies but are spread across global foundries, IDMs, OSATs, and equipment manufacturers.

On the other hand, Korean equipment and materials stocks are a bit different. Even with good technology, they are heavily influenced by the investment cycles of specific large customers like Samsung Electronics, SK hynix, and LG Display, and whether they pass their qualification tests. If US companies are closer to "companies that sell solutions to global process bottlenecks," Korean companies are often closer to "companies that localize or advance specific processes within the domestic memory/foundry supply chain."

This difference is important from an investment perspective. For US equipment and materials stocks, one must first look at their technological position and global market share. For Korean ones, in addition to technological prowess, one must also consider customer adoption, the speed of transition to mass production, localization trends, the CAPEX cycles of Samsung Electronics and SK hynix, and their investment direction in HBM and advanced packaging.

This doesn't mean that Korean equipment and materials stocks are less attractive. On the contrary, as AI semiconductors move towards HBM, chiplets, hybrid bonding, CoWoS, PLP, CXL, and high-performance SSDs, new opportunities are opening up for Korean companies as well. Companies that were previously tied to front-end and memory cycles can now be re-evaluated based on more specific bottlenecks like advanced packaging, HBM testing, nano-metrology, laser annealing, cleaning/CMP, specialty gases, and test sockets.

The core idea I'm focusing on now is simple.

Instead of chasing expensive AI leaders, find the essential bottlenecks that become more critical as AI semiconductors grow more complex.

In the US, companies like $ACLS, $VECO, $ONTO, $ACMR, $COHU, $MKSI, $ICHR, $AEHR, $ENTG fit this perspective. So, which companies in the Korean market are on a similar trajectory? While there isn't a perfect 1:1 correspondence, looking at it by process reveals some quite interesting candidates.

1. Korean Equipment & Materials Candidates Corresponding to US Peers

There is one point to be cautious about here. Korean companies often don't have a "perfect 1:1 correspondence" with their US counterparts. US equipment makers have a globally broad product portfolio, while Korean equipment and materials companies often have a high dependency on specific customers, especially Samsung Electronics and SK hynix. Therefore, for the Korean version, one must look at technology + customer qualification + localization/supply chain internalization + expansion cycles all together.

2. Key Korean Equipment & Materials Candidates I'm Watching First

A-List: Top Candidates to Watch

These 8 companies connect most naturally with the US ACLS-type thesis.

3. Detailed Analysis

1) $K039030 EOTechincs

The Closest Candidate to a Korean $VECO

EOTechincs is the first company that comes to mind in Korea when looking at laser-based semiconductor equipment. It's not just a simple marker equipment company but has expansion potential into laser annealing, laser cutting, grooving, debonders, and UV drillers.

A Samsung Securities report explained that EOTechincs contributes to DRAM scaling in the front-end process through its laser annealing equipment, and in the back-end, it possesses equipment that contributes to Advanced Packaging, such as laser grooving, debonders, and UV drillers.

The report also mentions a forecast for increased semiconductor equipment sales in 2026, the potential adoption for 400+ layer NAND, and shipments of grooving equipment for HBM4/OSATs.

Investment Points

• Laser annealing = A key theme like $VECO
• Potential for expansion into HBM4, high-stack NAND, and Advanced Packaging
• Strong process specialization in laser equipment
• Has a distinct "niche equipment stock" character among Korean peers

Risks

• The stock price may have already priced in expectations for laser equipment
• Customer qualification and mass production timing are crucial
• Need to separate the growth potential of new equipment from existing businesses like markers and displays

My Take: If I were looking for the Korean version of $VECO, I would look at $K039030 EOTechincs first.

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2) $K403870 HPSP / $K122640 YEST

High-Pressure Hydrogen Annealing: Different from VECO, but Important as an "Annealing Bottleneck"

HPSP doesn't do laser annealing, but it has a very specialized equipment area in high-pressure hydrogen annealing. According to KIRS data, HPSP is a company specializing in high-pressure hydrogen annealing equipment.

However, there have been recent reports that YEST made its first shipment of high-pressure hydrogen annealing equipment to a global semiconductor company, suggesting HPSP's monopoly could be broken.

Investment Points

• HPSP: The leading company in high-margin, high-pressure hydrogen annealing equipment
• YEST: A latecomer, but with the potential to crack the monopoly structure
• Linked to scaling in logic/memory and process advancement

Risks

• HPSP already trades at a high premium
• YEST needs to prove its earnings stability and mass-production references
• Both should be viewed under the "annealing" theme rather than "laser"

My Take: HPSP is a good company but faces valuation pressure. YEST has optionality but requires more validation. In terms of stability, HPSP; for asymmetry, YEST.

3) $K140860 Park Systems

The Korean $ONTO, a Textbook Metrology Equipment Play

Park Systems is an AFM-based nano-metrology company. As HBM, hybrid bonding, and advanced packaging become more important in AI semiconductors, the need to precisely measure surface roughness, step height, bonding quality, and micro-defects grows.

In its product description for Advanced Packaging, Park Systems presents a solution combining AFM and WLI, explaining its use in front-end, back-end, and advanced packaging metrology.

Recent reports have also mentioned expectations for full-scale orders of its NX-TSH metrology equipment for cutting-edge packaging like 2.5D, and the potential for increased AFM demand in the sub-2-micrometer measurement range, which is difficult for existing optical equipment to handle.

Investment Points

• Beneficiary of hybrid bonding and advanced packaging metrology
• High-precision metrology based on AFM, distinct from optical inspection
• Potential to expand its global foundry/IDM customer base
• Most similar to the metrology character of $ONTO

Risks

• Already recognized as a high-quality company with a market premium
• Equipment order timing could be slow
• Production capacity and lead time management also need to be checked

My Take: Park Systems is the highest-quality metrology equipment candidate among Korean equipment and materials stocks. If the price is right, it's the most comfortable long-term candidate.

4) $K348210 Nextin

An Aggressive Candidate in HBM, Chiplet, and Hybrid Bonding Inspection

Nextin is expanding from its traditional wafer inspection business into back-end and advanced packaging inspection. This point is very important.

Nextin has launched Asper, an advanced packaging inspection tool targeting HBM and 2.5D packages. It has been reported that it can detect defects as small as 50nm using 2D imaging technology and AI algorithms.

Additionally, IRIS-III was introduced as equipment specialized for detecting non-metallic voids in W2W and C2W bonding processes.

Regarding Croki, its back-end inspection equipment for HBM, there have been reports of sample deliveries to Samsung, Micron, and Intel, as well as a contract with SK hynix.

Investment Points

• HBM, chiplet, and hybrid bonding inspection equipment
• Expanding from front-end inspection dependency to the back-end
• A candidate closely resembling the inspection/metrology bottleneck theme of ONTO
• Potential for customer diversification

Risks

• Still need to confirm the revenue contribution from each product
• High order volatility
• Need to check China sales exposure and customer concentration

My Take: If Park Systems is a "high-quality metrology stock," Nextin is an "advanced packaging inspection growth stock." For a more aggressive play, Nextin is more interesting.

5) $K098460 Koh Young / $K064290 Intekplus / $K420770 Gigavis

Candidates Expanding into Packaging and Substrate Inspection

These three companies are all in the inspection equipment space.

Koh Young is leveraging its experience as the world's No. 1 in 3D SPI/AOI to expand into advanced packaging inspection equipment. At SEMICON Korea 2026, it introduced advanced packaging inspection equipment and industrial AI inspection solutions, and its status as the global market share leader in SPI/AOI was also mentioned.

Intekplus is a machine vision-based appearance inspection equipment company. The possibility of its entry into the HBM advanced packaging module appearance inspection market has been reported, and supply discussions with SK hynix have been mentioned.

Gigavis is a candidate for semiconductor substrate inspection equipment. As AI semiconductors move towards large-area packages and high-performance substrates, the demand for substrate defect inspection could increase.

My Take

• Koh Young: Inspection technology prowess and AI inspection expandability
• Intekplus: An option for HBM module/substrate appearance inspection
• Gigavis: A smaller candidate in substrate inspection

I would place these as secondary candidates to Park Systems and Nextin. However, they are worth watching together when the advanced packaging inspection theme broadens.

6) $K319660 PSK

A Quiet Giant, Close to a Korean $ACMR

PSK has global competitiveness in Dry Strip equipment. According to PSK Group's IR materials, it holds over 40% of the global market share in the dry strip equipment field, and it has secured Samsung Electronics, SK hynix, Intel, and Micron as customers.

The more interesting part is the potential for its use in TSMC's CoWoS process. According to a report by TheElec, PSK is in discussions with TSMC to supply its PR removal equipment, SUPRA, which is linked to the RDL patterning process in CoWoS.

PSK's product descriptions show that it also has a lineup of equipment for wafer edge and residue removal, such as NHM strip, Bevel etch, and Edge clean.

Investment Points

• Global leader in Dry Strip
• Potential to enter CoWoS/advanced packaging
• Beneficiary of the recovery in memory front-end capex
• Partially linked to the wet/cleaning theme of $ACMR

Risks

• CoWoS/TSMC supply is still in the discussion/validation stage
• Sensitive to customer capex cycles
• A re-rating may have already occurred

My Take: PSK is one of the "quietest but most comfortable equipment stocks" among Korean peers. While not a flashy, direct HBM play, it's worth looking at as a process bottleneck equipment provider.

7) $K281820 KC Tech

CMP, Cleaning, Slurry: A Mix of ACMR/ENTG Characteristics

For KC Tech, one must look at its CMP equipment, cleaning equipment, and CMP materials together. According to the company's product description, it possesses Batch-type cleaning systems and CMP equipment.

In HBM and advanced packaging, the importance of planarization and cleaning continues to grow. CMP is not a flashy type of equipment, but it is directly linked to yield. Cleaning is also a key process for reducing micro-contamination.

Investment Points

• CMP equipment + cleaning equipment + CMP materials
• Increasing importance of planarization and cleaning in HBM/advanced processes
• The combination of both equipment and materials is an advantage

Risks

• Competes with large global CMP equipment makers
• Customer adoption and the pace of localization are important
• Growth rate may not be explosive

My Take: KC Tech is a Korean-style candidate that sits between $ACMR and $ENTG. It's less aggressive but can be a steady beneficiary of process advancements.

8) $K089030 Techwing / $K232140 YC / $K092870 Exicon / $K253590 NEOSEM

The Korean $COHU/$AEHR Test Basket

This group is in test equipment. In the AI/HBM era, testing becomes critically important. HBM needs to be tested before stacking, during stacking, and after stacking. The same goes for SSDs, CXL, and high-performance memory.

For Techwing, the HBM cube prober is key. According to reports, Techwing's cube prober is being supplied to Samsung Electronics and has also passed the final qualification test for SK hynix's HBM cube probe.

YC can be seen for memory test equipment, Exicon for memory/SSD testing, and NEOSOM for SSD and CXL testing. They all resemble the "test bottleneck" theme of $COHU and $AEHR.

My Take

In this group, I would consider Techwing as the top priority because it is most directly linked to HBM.

9) $K095340 ISC / $K058470 Leeno Industrial

Test Sockets & Probe Pins: Consumable Test Infrastructure

ISC and Leeno Industrial are more in the test socket and probe pin space than equipment. However, as AI semiconductors grow larger and more complex, the importance of test sockets increases.

At SEMICON Korea 2025, ISC unveiled its AI test solution and a glass substrate test socket, WiDER-G, and its potential application for next-generation advanced packaging like glass substrates and CoWoS was introduced.

Investment Points

• AI/HBM/ASIC test sockets
• Consumable-based revenue structure
• Potential for ASP to rise with changes in advanced packaging

Risks

• Customer adoption and product mix are important
• Leeno Industrial already trades at a high premium
• For ISC, need to confirm its business direction and earnings recovery after the SKC acquisition

My Take: If you want "consumable test infrastructure" rather than equipment, ISC and Leeno Industrial are good choices. However, in the current logic, ISC is more directly tied to HBM/AI packaging.**

10) $K045100 HANYANG ENG

Gas & Chemical Supply Infrastructure, Close to a Korean $ICHR

HANYANG ENG is in semiconductor and display facilities, ultra-high purity (UHP) piping, and CCSS. According to KIRS data, HANYANG ENG specializes in piping facilities and CCSS for semiconductors, displays, and industrial plants. It was the first in Korea to succeed in localizing the entire process for UHP piping for semiconductors and displays, as well as localizing CCSS.

The company brochure also describes CCSS as equipment that provides integrated management for the entire process of supplying, transporting, mixing, and disposing of ultra-precision chemicals.

Investment Points

• Essential infrastructure for semiconductor fab expansions
• Gas and chemical supply systems
• Linked to Samsung Electronics and SK hynix capex
• Most similar to the delivery subsystem business of $ICHR

Risks

• More of a facilities/engineering company than an equipment maker
• Margins may be lower than high-value-added equipment stocks
• Project-based revenue fluctuations

My Take: If you're looking for a company like $ICHR in Korea, HANYANG ENG is the first that comes to mind. However, it should be viewed as a play on fab infrastructure leverage rather than a high-margin niche equipment stock.

11) $K104830 Wonik Materials / $K074600 Wonik QnC / $K166090 Hana Materials / $K064760 TCK / $K357780 Soulbrain / $K005290 Dongjin Semichem

The Korean $ENTG: A Basket of Materials, Parts, and Contamination Control

ENTG is in filters, materials, and contamination control. In Korea, it's better to view this as a basket of materials and parts companies rather than a single corresponding company.

Wonik Materials is a high-purity specialty gas company. According to its company profile, it has localized high-purity specialty gases that were previously highly dependent on imports for the semiconductor and display industries, and has secured a product lineup of over 100 items.

Wonik QnC is in quartz, Hana Materials and TCK are in Si/SiC parts, and Soulbrain and Dongjin Semichem can be seen as being in the chemicals and materials space.

My Take

This group consists of "consumable supply chain stocks" rather than explosive equipment stocks. They make sense as a long-term basket if the price is right.

4. My Recommended Korean Equipment & Materials Watchlist

1st Tier: Stocks to Watch with Highest Priority

2nd Tier: Candidates to Track Alongside

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