UBmaterials close to commercializing CMP slurry 

South Korean semiconductor materials start-up UBmaterials has developed a slurry used for the chemical mechanical polishing (CMP) process in chip production, TheElec has learned.

The slurry was co-developed by South Korean memory giant SK Hynix. Development is, however, at this time partially complete and is being prepared to be applied at the memory company’s 3D NAND Flash production line at Cheongju.

It will be applied for commercial production later this year at the earliest and within the first half of 2021 at the latest, people familiar with the matter said.

However, the slurry is still up for final review and it is possible for the commercial application being delayed or scrapped all together. 

In the CMP process, metal wiring or insulating films are flattened out. Wafers are placed on a CMP pad and slurry is dripped in between. The pad then spins to flatten the wafer out.

Semiconductor production boils down to exposure, deposition and etching. Every time a new layer is added, there needs to be added flattening out process afterwards. Different slurry are used for flattening different components. For insulating films, oxide slurry is used. For metal wiring, metal slurry is used. 

Silica (SiO2) and ceria (CeO2) are used as oxide slurry and copper (Cu), aluminum (AI) and tungsten (W) are used as metal slurry.

UBmaterials’ slurry uses tungsten. Tungsten has higher permittivity compared to copper, making it more conductive for electricity. It is slowly replacing the widely used copper and seeing more use for 3D NAND Flash production.

The world leader in CMP slurry was the US’s Cabot Microelectronics, which has unrivaled technology in tungsten CMP slurry, people familiar with the matter said. If UBmaterials succeed in commercializing its CMP slurry, it will be another success story like those of Dongjin Semichem, they said.

Samsung Electronics and SK Hynix were also looking to expand the use of CMP slurry from local suppliers, they said. SK Hynix was reviewing CMP slurry made by affiliate SKC as well, they said. Samsung Electronics was expanding to use of slurry from affiliate Samsung SDI.

SK Hynix chose UBmaterials as a “technologically innovative company” in its start-up support program back in 2018, when Hanyang University professor Paik Un-gyu was the Minister of Trade, Industry and Energy. SK Hynix provides support in technology development and review as well as interest-free loan and guarantee purchases for companies selected in the program.

UBmaterials was valued at 50 billion won in late 2018 and received large amounts of funding. KOSDAQ-listed Mecaro loaned 1.5 billion won to the company. UBmaterials’ largest shareholder is Hanyang University professor and chairman of the Korean Society of Semiconductor & Display Technology Park Jae-geun, who has a 22.82% stake in the company. Japan’s Shin-Etsu Chemical in the second largest shareholder with 18.54% stake.