Annealing and doping-dependent magnetoresistance in single layer poly(3-hexyl-thiophene) organic semiconductor device
Annealing and doping-dependent magnetoresistance in single layer poly(3-hexyl-thiophene) organic semiconductor device
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DOI：
10.1016/j.orgel.2014.11.019
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发表时间：
2015-02
影响因子：
3.2
通讯作者：
Hang Gu;Shankui Chang;David F. Holford;Tingting Zhang;Haizhou Lu;T. Kreouzis;W. Gillin
中科院分区：
文献类型：
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作者：
Hang Gu;Shankui Chang;David F. Holford;Tingting Zhang;Haizhou Lu;T. Kreouzis;W. Gillin
在真空条件下，在玻璃化温度为150℃以上的条件下，比较了聚3-己基噻吩（P3HT）器件（Au/P3HT(350 nm)/Al）在退火前后的电流密度-电压（J-V）和磁导率（MC）响应。通过退火脱掺杂后，由于电荷注入势垒的增加，电流密度降低了3个数量级以上。根据双极化子机制，退火后负MC响应的增加（接近1个数量级）可以用去掺杂引起的费米能级的移动来解释。我们通过光氧化再掺杂成功地调整了电荷注入势垒。这导致电荷注入和输运随着偏置的增加从单极向双极转变，我们使用双极化子和三极化子相互作用机制的组合来模拟MC响应。
We compare the current density–voltage (J–V) and magnetoconductance (MC) response of a poly(3-hexyl-thiophene) (P3HT) device (Au/P3HT(350 nm)/Al) before and after annealing above the glass transition temperature of 150 °C under vacuum. There is a decrease of more than 3 orders of magnitude in current density due to an increase of the charge injection barriers after de-doping through annealing. An increase, approaching 1 order of magnitude, in the negative MC response after annealing can be explained by a shift in the Fermi level due to de-doping, according to the bipolaron mechanism. We successfully tune the charge injection barrier through re-doping by photo-oxidation. This leads to the charge injection and transport transitioning from unipolar to ambipolar, as the bias increases, and we model the MC response using a combination of bipolaron and triplet-polaron interaction mechanisms.