Introduction

An Automated Material Handling System (AMHS), also known as an overhead hoist transport system, is a key part of semiconductor manufacturing. It is used to transport wafer carriers between production tools according to the process flow.As semiconductor processes continue to advance, wafer sizes have increased over time. The industry has moved from 6-inch and 8-inch wafers to 12-inch wafers, with diameters of 150 mm, 200 mm, and 300 mm. In addition, 450 mm (18-inch) wafers are under long-term planning. As wafer sizes increase, the weight of wafer carriers also increases. A fully loaded Front Opening Unified Pod (FOUP) typically weighs between 8 and 15 kg. Manual handling can no longer meet the requirements of modern production.

AMHS offers advantages such as automation, high efficiency, high stability, and intelligent operation. It enables wafers to be transported quickly and accurately to their destinations. This improves production efficiency, reduces labor costs, increases throughput, and enhances operational stability. As a result, AMHS has become an essential material handling system in semiconductor manufacturing.

1.What Is the Application of AMHS in the Semiconductor Industry？

1.1 Structure of the AMHS System

As shown in Figure 1, the AMHS has a complex system structure. It mainly consists of a hardware system and a software system [1].

Figure 1 AMHS System [1]

(1) Hardware System

The hardware system is the execution layer of AMHS. It is used for the automated transport, storage, and buffering of wafer carriers and reticle carriers in semiconductor cleanrooms. Overall, the hardware system mainly consists of transport equipment, storage equipment, and buffering and purge equipment. Together, these components form a three-dimensional logistics network that covers process tools, storage units, and fab space.

• Overhead Hoist Transport (OHT): OHT is the core transport equipment in an AMHS, operating on overhead rail systems in cleanrooms for long-distance and high-frequency wafer carrier transport. It directly interfaces with the loadports of process tools or storage equipment, enabling material transfer without occupying floor space. OHT is the primary transport solution in 300 mm wafer fabs.

• FOUP / Pod Stocker: FOUP/Pod Stockers are used for centralized storage and management of wafer carriers, which support automated storage, retrieval, and buffering of carriers. These systems typically adopt multi-level structures to increase storage density within limited space. They also provide buffering capacity under high-load production conditions.

• Reticle Stocker: Reticle Stockers are mainly used for centralized storage and management of reticle carriers, which are commonly deployed in lithography areas. These systems support reticle protection and scheduling to meet the high cleanliness and safety requirements of lithography processes.

• Reticle Cabinet: Reticle Cabinets are usually placed near lithography tools. They are used for nearby storage of reticle carriers. This shortens reticle retrieval paths and improves lithography process efficiency.

• Near Tool Buffer(NTB): NTB is installed near process tools and is used for short-term buffering and circulation of wafer carriers. By providing front-end buffering, NTB reduces waiting time for transport systems and improves continuous tool operation.

• Overhead Buffer Purge (OHBP): Used to supply clean, controlled gas (typically CDA or nitrogen) to carriers such as FOUPs while they are stored or transported on the overhead track (e.g., OHT system). Its main function is to maintain a clean and stable environment inside the carrier by preventing moisture, oxygen, or particle contamination.

• Tower Stocker: Tower Stockers adopt a vertical structure for high-density storage of wafer carriers. They are suitable for applications with limited floor space or centralized storage requirements.

• Loadport Station (LPS): A manual station in an AMHS is a point where operators can manually load or remove carriers from the automated system. It serves as a transit station between manual loading and OHT loading, allowing carriers to be transferred into the automated transport system.

• Tool Loadport Purge (TLP): TLP is used for environmental control at tool loadport areas. By purging and controlling the local environment, it reduces contamination risk during wafer carrier loading and unloading.

• Autonomous Mobile Robot (AMR): AMR is mainly used in specific areas that require high flexibility. It serves as a supplement to overhead transport systems and enables ground-based carrier transport.

• Electronic Rack (E-Rack): E-Racks are used for storage and management of electronic materials or related auxiliary items. They help improve standardization and traceability in material management.

(2) Software System

The software system is the control core of AMHS. It is responsible for unified scheduling and management of the hardware system.

• Material Control System (MCS): MCS receives transport commands from the Manufacturing Execution System (MES). It performs unified scheduling of transport equipment, storage equipment, and buffering equipment. This enables automated operation of material handling processes.

• Manufacturing Execution System (MES) Interface: The MES interface enables data exchange between AMHS and the Manufacturing Execution System. It supports coordination between production planning and material handling.

1.2 Application of AMHS in the Semiconductor Industry

AMHS has been increasingly adopted in the semiconductor industry due to its advantages in automation, efficiency, stability, and intelligent operation. Wafer fabrication remains the primary application area for AMHS. In 12-inch and larger wafer fabs, AMHS has become a standard configuration, while its penetration rate in 8-inch fabs continues to increase. This is mainly because AMHS enables fast and accurate wafer transport, significantly improving production efficiency, shortening cycle time, increasing throughput, and enhancing system stability. As wafer manufacturing upgrades from 8-inch to 12-inch and larger production lines, process flows become more complex, making AMHS a key infrastructure for fab automation and capacity expansion.

In the advanced packaging sector, the adoption of AMHS is also accelerating. Driven by global digitalization and the increasing number of integrated circuits, demand from consumer electronics, automotive, and industrial applications continues to grow, expanding the overall packaging market. In 2024–2025, the global semiconductor packaging market exceeded approximately USD 39.5–49.8 billion, with the share of advanced packaging steadily increasing[2]. To support high-throughput and high-reliability production, advanced packaging fabs are increasingly introducing AMHS to improve material handling efficiency and yield performance.

AMHS is also being introduced in the compound semiconductor sector. Compound semiconductor wafers, such as GaAs, InP, GaN, and SiC, are generally more fragile than silicon wafers, and manual handling can significantly increase breakage rates. As the compound semiconductor industry continues to grow and production automation advances, demand for AMHS in this field is rising to reduce handling risks and improve production stability.

2. What Is the Market Status of AMHS in the Global Semiconductor Industry？

2.1 Global Semiconductor AMHS Market Size

According to market research data, the global semiconductor AMHS market was valued at approximately USD 3.1–3.5 billion in 2024 and is projected to reach around USD 6.2–6.8 billion by 2033–2034, with a compound annual growth rate (CAGR) of about 7–8%[3].

From the demand side, as shown in Figure 2, the Asia-Pacific region represents the largest market for semiconductor AMHS, accounting for approximately 74% of the global market. North America and Europe follow, with market shares of about 16% and 8%, respectively [4]. The Asia-Pacific region—particularly Taiwan, South Korea, mainland China, and Japan—hosts the world’s core semiconductor manufacturing bases. Advanced logic processes and memory device manufacturing are largely concentrated in this region.

Figure 2 Global AMHS Market Demand Distribution

From the supply side, as shown in Figure 3, the global AMHS market is primarily dominated by suppliers from Japan and South Korea. Among them, Murata Machinery and Daifuku hold market shares of 48.3% and 39.4%, respectively, accounting for a combined 87.7% of the global AMHS market. This indicates a highly concentrated market structure, particularly in the 300 mm wafer fab segment, where these suppliers hold an almost monopolistic position.

Figure 3 Competitive Landscape of the Global AMHS Market

2.2 Major AMHS Manufacturers and Solution Providers

2.2.1 Murata Machinery (Japan)

Murata Machinery was founded in 1935. In 2008, it acquired AGVE AB of Sweden and Horibe Machinery of Japan. According to available data, Murata Machinery reported total revenue of USD 11.68 billion in 2023, of which semiconductor AMHS system revenue reached USD 1.44 billion, representing a year-on-year increase of 9%. In 2023, Murata Machinery’s AMHS revenue surpassed that of Daifuku, making it the largest AMHS system supplier globally.

2.2.2 Daifuku Co., Ltd. (Japan)

Daifuku was established in 1937 and is one of the world’s largest logistics and material handling system manufacturers. According to available data, Daifuku reported total revenue of USD 4.35 billion in 2023, with semiconductor AMHS system revenue of USD 1.17 billion, accounting for 26.9% of its total revenue and representing a year-on-year decrease of 11.7%. In 2023, Daifuku’s global market share in semiconductor AMHS systems reached 39.4%, ranking second worldwide. Daifuku benefits from long-standing customer trust and extensive technical experience accumulated over many years.

2.2.3 SEMES (South Korea)

SEMES was founded in 1993 and is a wholly owned subsidiary of Samsung Electronics. It is the largest equipment manufacturer in South Korea and primarily supplies OHT and other key logistics automation equipment for Samsung Electronics’ mass production semiconductor lines. According to available data, SEMES recorded semiconductor AMHS system revenue of USD 3.34 billion in 2023, representing a year-on-year decrease of 25.1%, and accounting for approximately 11.2% of the global semiconductor AMHS market.

2.2.4 Meet Future Technology (China)

Meet Future Technology is one of the representative Chinese providers of AMHS solutions for semiconductor wafer fabs. The company offers integrated solutions covering overhead transport systems (OHT), storage and buffering equipment, and material control systems (MCS), addressing key material transport requirements in advanced semiconductor manufacturing.

With the continued expansion of semiconductor fabrication capacity in mainland China, Meet Future Technology has been involved in selected new fab construction and capacity expansion projects, particularly in 300 mm wafer manufacturing environments, where system reliability and integration capability are critical. Industry analyses indicate that domestic AMHS solution providers are increasingly participating in localized automation deployments, contributing to greater supply chain diversification in the global AMHS market.

3. What Are the Development Trends of AMHS in the Semiconductor Industry?

3.1 Technological Innovation Driving the Continuous Development of AMHS

As semiconductor processes advance, wafer sizes have evolved from 6-inch and 8-inch to 12-inch, leading to larger fabs and increasingly complex process flows. AMHS has developed accordingly. For example, cleanroom monorail transport systems can extend over 200 kilometers and operate more than 10,000 vehicles. Because processing times vary across different steps, transport vehicles may accumulate around certain tools, causing congestion and reducing productivity[5]. To address this challenge, artificial intelligence (AI) is being introduced into AMHS control software to predict congestion and optimize routing, thereby improving overall transport efficiency.

3.2 Safety, Efficiency, and Stability as Core Requirements for AMHS

Semiconductor manufacturing is highly automated and requires AMHS to operate continuously, 24 hours a day throughout the year. Given the high value and fragility of wafers, strict requirements are placed on transport precision and system stability. For example, overhead hoist transport systems must operate with minimal vibration during movement and handling to avoid contamination and productivity loss, and AMHS products are typically expected to achieve reliability levels close to 99.999%. In addition, the expansion of fab scale places increasing demands on system speed and efficiency.

3.3 Persistent Industry Barriers

AMHS is a technology-intensive industry that integrates mechanical, electrical, and software engineering and requires a deep understanding of fab operating scenarios. On the hardware side, a single OHT vehicle may contain more than 2,000 components, including numerous sensors, placing strict demands on material selection, structural design, and rail layout to ensure stability and reliability at high speeds. On the software side, system complexity increases significantly as the number of vehicles grows. For example, managing 50 vehicles is fundamentally different from managing 500, requiring tailored solutions for scenarios such as vehicle intersections and task allocation. This demands not only strong software capabilities but also extensive experience in semiconductor fab automation.

4. Conclusion

As the “logistics backbone” of semiconductor fabs, AMHS has become an indispensable part of semiconductor manufacturing due to its advantages in automation, efficiency, stability, and intelligent operation. In particular, AMHS has become a standard configuration in large-diameter wafer fabs. With continuous advances in semiconductor technology, the role of AMHS continues to expand, calling for increased investment in research and development, stronger collaboration across the upstream and downstream supply chain, and enhanced talent development to build a complete industrial ecosystem and improve manufacturing efficiency and quality. Although the AMHS industry involves certain entry barriers, the rapid growth of the semiconductor sector and the expansion of downstream applications such as artificial intelligence, big data, automotive, and industrial fields are expected to drive strong market growth. Emerging technologies and new business models will continue to create potential opportunities for industry participants.

References:

[1] https://mp.weixin.qq.com/s/_VFMaRG3bpoCX36TdA -Q1w 

[2]Precedence Research (2024) AMHS for Semiconductor Market Size, Share and Forecast. Available at: https://www.precedenceresearch.com/amhs-for-semiconductor-market (Accessed: 2026).

[3]Grand View Research (2024) Semiconductor Packaging Market Size, Share & Trends Analysis Report. Available at:

https://www.grandviewresearch.com/horizon/outlook/semiconductor-packaging-market-size/global (Accessed: 2026).

[4] https://mp.weixin.qq.com/s/DwNCn3plgxJbYBXqFqHBMw 

[5] 吴立辉, 李元生, 周秀等. 晶圆制造 AMHS 防堵塞 路径规划方法研究 [J]. 计算机仿真, 2023, 40（11）: 284-289. DOI:10.3969/j.issn.1006-9348.2023.11.054