| Date | May 2011 | Marks available | 3 | Reference code | 11M.3.hl.TZ1.C5 |
| Level | HL | Paper | 3 | Time zone | TZ1 |
| Command term | Describe and Explain | Question number | C5 | Adapted from | N/A |
Question
Describe how silicon may be converted into a p-type semiconductor and explain why this leads to an increase in its electrical conductivit
Markscheme
doping with/adding small quantities of a Group 3 element (B, Al etc.);
atoms contain less electrons so give “positive holes”/“electron holes” (in the filled band);
these “holes” are able to move and hence allow the silicon to conduct / OWTTE;
Examiners report
Although many scored the mark for “adding a Group 3 element”, confused answers followed in about half of the responses.
