According to IHS, a 5" Full-HD AMOLED display now costs $14.3 (down from $17.1 in Q4 2015) - and now costs less than a similar LCD display ($14.7, down from $15.7 in Q4 2015). This is the first time an AMOLED costs less than an LCD.
IHS says that to make a 5" FHD LCD, the materials costs are $9.2 and non-material costs (including deprecation) s $5.4. For an AMOLED display, materials cost $7.2 and non material costs amount to $7.2.
While we're not sure if IHS is correct, AMOLED prices have been falling steadily. According to reports in December 2015, SDC did intend to lower its AMOLED prices to be more competitive than LCDs, but it's a bit strange they would price it below LCDs.
In any case, a 5" FHD AMOLED is not state-of-the-art. The 5.1" Super AMOLED used in the GS7 costs $55, according to IHS.
IHS explains that Samsung managed to lower the price because they enhanced their rate of operation (IHS says that SDC operates at 95% capacity now), increased their customers base - and some production line deprecation costs have ended.
Interestingly, in July 2014 DisplaySearch estimated that AMOLED prices will fall below LCD prices within 2 years - so perhaps they indeed got it right.