This link shows that South Korea is the largest spender of R&D in the world in terms of amount.
What drives them toward such enormous amount to be invested in R&D?
A 2016 piece in Nature appropriately titled "Why South Korea is the world’s biggest investor in research" situates these investments within its overall postwar economic development strategy:
the government set goals and then channelled money to corporate partners to carry them out. The formula was devised by Park's father, dictator Park Chung-hee, who seized power in a 1961 coup. During his 18-year reign, he favoured companies that grew into behemoths — conglomerates, called chaebol in Korea, such as Samsung, LG and Hyundai, which remain the backbone of the nation's economy today.
Powered by these industries, five decades of economic growth vaulted South Korea from developing-world poverty to membership of the group of 20 (G20) leading industrial nations. As the country moved painfully from dictatorship to democracy, government support for research remained a bipartisan priority — mainly as a driver for further growth. Korea's corporate giants still dominate the R&D scene. According to KISTEP figures, of the 63.7 trillion won spent on R&D in 2014, 49.2 trillion came from private enterprises. That includes more than half of the 11.2 trillion won spent on basic research. Much industrial research happens behind closed doors, although partnerships with academia are on the rise.
This is quite similar to Japan in many respects, but as a smaller country, South Korea has had to invest in R&D at a higher percentage of GDP to catch up.
South Korea is home to some of the largest technology corporations in the world. Samsung (which doesn't just create consumer electronics, but also construction machinery and services, and even insurance services) is one of the largest R&D spenders in the world, and they alone account for a large portion of South Korea's total R&D spending. In 2019, Samsung invested $16 billion in R&D or about 20% of South Korea's total.
Among the other large R&D spenders in South Korea are LG ($3+ billion), Hyundai (~$3 billion), KIA ($1 billion), Celltrion ($3 billion), and several others. All of the companies I listed acount for nearly half of all corporate R&D spending in South Korea. The South Korean Government, through various institutions and grants, invests anywhere from $15-20 billion a year in R&D which isn't exactly earth shattering and is very much in line with that of other majored developed countries like the US or Japan.