[Peace&Chips] 'OHT' Supporting Semiconductor Production Automation... Expansion of Korean Products Amid Japan's Dominance

OHT Moving Wafers Along Ceiling Rails
About 1,850 Units Only at Samsung Pyeongtaek Campus P1
Samsung Electronics and SK Hynix Use Domestic OHT

Editor's NoteSemiconductors, known as the rice of modern industry. Although it's a term we hear every day, it's often hard to explain. Peace & Chips will make the complex concepts and overall flow of the semiconductor industry easy to digest for you. Just bring your spoon.

[Asia Economy Reporter Kim Pyeonghwa] If you have visited a university hospital, you might have seen this equipment. It is a box-shaped device that moves along rails on the ceiling, and in hospitals, it is called a cart. It is used to transport various specimens and blood samples in places like emergency rooms and blood collection rooms. It acts as the hands and feet of medical staff in the busy university hospital environment.

This kind of equipment is also used in semiconductor factories that operate 24/7. It is called the Overhead Hoist Transport (OHT). The OHT plays a crucial role from the thin wafer stage to the creation of tiny semiconductor chips the size of a fingernail. It moves FOUPs (Front Opening Unified Pods) containing wafers along ceiling rails according to the production steps.

Inside the semiconductor factory, an OHT moves along the rail on the ceiling / [Photo by SK Hynix Newsroom]

Although the OHT may seem to perform simple tasks, it is a key device driving factory automation. Since hundreds of processes are involved before a finished product is completed, tens of thousands of transport operations occur. If humans had to handle all these, the required labor and time would be enormous.

Due to the large workload, many such devices are used in factories. In fact, Samsung Electronics’ Pyeongtaek Campus Line 1 (P1) reportedly has about 1,850 OHT units. Each costs around 40 million KRW, comparable to a mid-sized car like the Grandeur. The speed is fast at 5 meters per second, and sensors prevent collisions between moving OHTs.

The OHT was originally dominated by Japan. Japanese company Daifuku led the OHT market, and its sales volume was 512.2 billion yen (approximately 4.8855 trillion KRW) for the 2021 fiscal year (April 2021 to March 2022). Daifuku counts major semiconductor companies such as Samsung Electronics, SK Hynix, and Taiwan’s TSMC among its clients.

OHT product made by Semes. The interior is designed to stack and transport multiple wafers. /
[Photo by Semes website]

In Korea, dependence on Daifuku was high, but the situation has changed in recent years. A wave of OHT localization has led to technological development by domestic companies such as Semes and SFA. The 2019 Japanese export restrictions, which increased demands for localization of items highly dependent on Japan, also accelerated this trend.

Currently, both Samsung Electronics and SK Hynix use domestically produced equipment in their Korean factories. Samsung Electronics uses OHTs made by its subsidiary Semes. For example, all OHTs in Pyeongtaek Campus P1 are supplied by Semes. SK Hynix also uses domestic OHTs in some of its processes.

This article is from [Peace & Chips], published weekly by Asia Economy. Click subscribe to receive articles for free.

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