金属氧化物半导体场效应晶体管测量面罩对表面剂量的影响

An investigation about the effect of masks on surface dose by using MOSFET detector

目的使用金属氧化物半导体场效应晶体管（metal oxide semiconductor fiel deffect transistor，MOSFET）探测器测量面罩对表面剂量的影响。方法选用6MV和15MVX射线进行照射，分为有面罩组和无面罩组，用MOSFET分别测量，每组测5次，共测量5种不同密度的面罩。结果使用面罩后表面剂量明显增加；不同面罩对表面剂量的影响程度不同。结论使用面罩后射线的剂量建成区出现变化，表面剂量明显提高。临床治疗中需要适当关注皮肤表面的放射反应。

Objective To measure the effect of masks on surface dose for the use of MOSFET detector. Methods The experimental objects were irradiated with 6 MV and 15 MV X-rays and the objects were divided into masked group and non-masked group before exposure. The dose measurements of each group was measured for 5 times and 5 types of masks of different density were measured by using MOSFET detector, Results The surface dose increases significantly after applying the mask ; and different types of masks have identical effect on it, Conclusion The dose build-up regions have changed and surface dose increases considerably after the application of masks, Hence, proper attention should be paid to the radiation effects of the skin surface in clinical therapy,