See if you want to be a Research and Development Scientist then I would recommend you to go for the Applied physics field. See there are numerous application of Physics in Technology, so you can go for the R&D in Semiconductor Physics, Solid State Physics/Condensed Matter physics/Material science, Nuclear and Atomic Physics, Medical Physics, Geophysics, Laser and Wave optical physics, Biophysics, Energy Physics. All of this specializations have a lot of scope in R&D sector and if you can study this specialization in Master's/PhD then you will get enough exposure to become a R&D scientist.

For more information regarding Physics consider the link below:

https://dqxeclau.top/courses/physics-course

I hope this helps. Wish you a great day!