On the rear there are a number of philips screws which once removed open up the controller. You can see the vibration motors with their offset weights. There are two PC’s the small one holds the two primary joysticks, and is screwed down onto a larger board.
From experience I found out that removing glob top to expose a clean die is actually harder than removing the plastic in a standard ic package. This one was no exception, even with extended hot Sulphuric Acid action, the quality of the die photo is a bit marginal with some glob top residue around.
I was expecting a small MCU, but what we have here is (2.3mm x 2.56mm) 44 pin digital logic ASIC – not that interesting to look at (Sometimes the die are a bit plain vanilla). There looks to be a small memory down the left side (ROM, or SRAM, the metal layout is too dense to be able to distinguish). Similarly in the main digital section the metal layout is pretty dense and obscuring any view of the transistors. I think there are just two metals, and my best guess for process node is 1.25μm so pretty old school CMOS really.
G6108D does not turn up very much, and Googling Luen Keung turns up only a few things. It does return as a name of a private Hong Kong company, so that’s my best guess for who designed this. As I have shown in other teardowns it is not unusual for a designer to list initials on the chip, but have never seen a designer print their full name, so am doubting the Luen Keung is an individual designer of this chip.