Shares in Welsh semiconductor company IQE have surged on the back of some bullish director dealings by the company's senior executives.Chief executive Drew Nelson, chief financial officer Phil Rasmussen and chief operating officer Howard Williams shelled out a combined £420,000 at 12.75p.The shares bounced 18% on Tuesday from their lowest point since 2009 to 14.75p as investors followed the trio's bargain hunting.The shares are still around half their 12-month high and well off their three-year highs above 36p.A late-September trading update showed first half revenue of £52m was in line with the July trading update, down 17% year-on-year as a result of strong currency headwinds and the wireless destocking at the end of 2013, but with earnings rising thanks to early benefits from acquisition synergies and economies of scale.The company's newer Photonics division delivered 13% growth, showing a positive move towards a more diverse revenue base.Top Director BuysIQE (IQE) Director name: Dr Andrew W NelsonAmount purchased: 1,800,000 @ 12.75p Value: £229,500Chariot Oil & Gas Ltd. (CHAR) Director name: Mr Adonis PouroulisAmount purchased: 1,029,096 @ 10.50p Value: £108,055IQE (IQE) Director name: Mr Phil RassmusenAmount purchased: 750,000 @ 12.75p Value: £95,625IQE (IQE) Director name: Dr Howard Robert WilliamsAmount purchased: 750,000 @ 12.75p Value: £95,625Macfarlane Group (MACF) Director name: Mr Bob McLellanAmount purchased: 78,791 @ 38.50p Value: £30,335Macfarlane Group (MACF) Director name: Mr John LoveAmount purchased: 50,000 @ 38.25p Value: £19,125