Samsung is said to manufacture the SoC, which Qualcomm revealed during the unveil of the Snapdragon 820 would be built on a "leading-edge FinFET process." Samsung switched to a 14nm FinFET manufacturing process this year with the latest-generation Exynos SoC, which is used in the Galaxy S6 and Galaxy S6 edge.
This isn't the first time we're hearing about Samsung being a possible manufacturer for the Snapdragon 820. In April, a report out of Re/code — citing anonymous sources — suggested that Qualcomm was looking to shift production to Samsung from Taiwan's TSMC in a bid to regain the South Korean manufacturer as a client.
The Korean report states that HTC, Sony, and Xiaomi will be the first manufacturers to test the Snapdragon 820. The shift to a 14nm process would give Qualcomm the ability to design a more energy-efficient SoC, an issue that has plagued the chip vendor this year.
Source: Mobile-dad (translated)