QUESTION 13 When the size of a semiconductor particle or crystal decreases, the band gap energy remains the same goes to zero becomes 1 QUESTION 14 What fraction of the volume of each corner atom is actually within the volume of a face-centered cubic unit cell? 1/2 1/4 1/8 1/16 QUESTION 15 Blue LEDs are usually made of . gallium sulfide gallium nitride gallium arsenide gallium phosphide O gallium oxide