溶液法制备绝缘层及其性能的研究

发布时间：2018-03-08 16:26

本文选题：有机薄膜晶体管　切入点：PVP　出处：《江南大学》2015年硕士论文　论文类型：学位论文

【摘要】：绝缘层作为OTFTs的重要组成部分,其性能好坏直接影响着OTFTs的性能,因此,要想获得性能优良的OTFTs器件,好的绝缘层显得至关重要。本论文选用PVP作为绝缘材料,其介电常数较高、绝缘性能好,而且由于溶于有机溶剂,所以适合溶液法制备。通过将其制备成PVP薄膜以及MIS结构器件,并借助椭圆偏振光谱仪、半导体参数分析仪和阻抗分析仪对其光学性能和电学性能进行测试,探讨了溶剂蒸汽辅助旋涂和辅助退火对PVP绝缘膜性能的影响。具体研究内容主要包括下列几个方面:(1)通过改变匀胶机旋转速率以及旋涂时是否放置PGMEA,研究了旋涂速度和PGMEA蒸汽辅助旋涂对PVP膜的影响。发现增大匀胶速率或利用PGMEA进行溶剂蒸汽辅助旋涂均能使PVP膜变薄;而且相同厚度条件下,用PGMEA蒸汽辅助旋涂得到的PVP膜做成的MIS结构,其单位面积漏电流密度J比未经蒸汽辅助旋涂的要小。表明PGMEA溶剂蒸汽辅助旋涂能有效降低PVP膜厚度,并且提高PVP膜电学性能。(2)利用苯甲醚蒸汽对PGMEA蒸汽辅助旋涂获得的PVP膜进行辅助退火,通过改变蒸汽辅助退火时间研究了它对PVP膜的影响。经椭偏光谱测试和拟合分析,得到随着苯甲醚蒸汽辅助退火时间的增加,PVP膜的总厚度下降,粗糙层厚度先降低后增大,在10min时达到最低值;由这种膜构成的MIS结构的J-V特性测试结果显示,当电场强度取值为2MV/cm时,J由0min时的1.07×10-6 A/cm2降至10min时的6.85×10-8 A/cm2,再增至20min时的2.99×10-7 A/cm2。表明PVP膜经适当时间的溶剂蒸汽辅助退火后,能有效降低其表面粗糙度和陷阱密度,从而提高PVP膜性能。(3)通过改变苯甲醚蒸汽的相对蒸汽压,研究了溶剂相对蒸汽压对溶剂蒸汽辅助退火制备PVP膜的影响。经椭偏光谱测试和拟合分析,得到随着相对蒸汽压的增大,PVP膜总厚度(均小于30nm)和粗糙层厚度均降低,薄膜致密性得到改善。由这种膜构成的MIS结构的J-V特性测试结果显示,当蒸汽压由0.21增加至0.82时,2MV/cm时J由2.94×10-7 A/cm2降至4.2×10-8 A/cm2,其漏电机理在电场强度小于1MV/cm时为P-F效应,大于1MV/cm时为肖特基发射。而且在相对蒸汽压为0.82时可得到薄膜厚度仅约为20nm、单位面积电容达到145 n F/cm2的超薄PVP膜。
[Abstract]:As an important part of OTFTs, the performance of insulating layer directly affects the performance of OTFTs. Therefore, it is very important to obtain a good insulating layer in order to obtain a good OTFTs device. In this paper, PVP is chosen as the insulating material. Its dielectric constant is high, its insulation property is good, and because it is soluble in organic solvent, it is suitable to be prepared by solution method. By preparing it into PVP thin film and MIS structure device, and with the help of elliptical polarization spectrometer, The optical and electrical properties were tested by semiconductor parameter analyzer and impedance analyzer. The effects of solvent vapor assisted spin-coating and auxiliary annealing on the properties of PVP insulation film were discussed. The specific research contents include the following aspects: 1) the spin-coating was studied by changing the rotation rate of the rubber leveller and whether or not to place PGMEA at the time of spin-coating. The effect of speed and PGMEA steam assisted spin coating on the PVP film was found. It was found that the PVP film could be thinned by increasing the uniform adhesive rate or using PGMEA as solvent vapor assisted spin coating. Moreover, under the same thickness, the leakage current density J per unit area of the PVP film prepared by PGMEA steam assisted spin coating is smaller than that of the MIS film without steam assisted spin coating. It shows that the PGMEA solvent vapor assisted spin coating can effectively reduce the thickness of PVP film. The electrical properties of PVP films were improved. (2) the PVP films obtained by vapor assisted spin-coating of PGMEA were annealed by phenylene ether vapor. The influence of PVP films on PVP films was studied by changing the time of vapor assisted annealing. The results of ellipsometry spectrum test and fitting analysis were used. The results show that with the increase of the vapor assisted annealing time, the total thickness of the PVP film decreases, the thickness of the rough layer decreases first and then increases, and reaches the lowest value at 10 minutes, and the J-V characteristics of the MIS structure formed by the film are measured. When the electric field intensity is 2 MV / cm, the surface roughness and trap density of PVP film can be reduced effectively by solvent vapor assisted annealing at 20 min, from 1.07 脳 10 -6 A / cm 2 at 0 min to 6.85 脳 10 ~ (-8) A / cm ~ (2) at 10 min, and then to 2.99 脳 10 ~ (-7) A / cm ~ (2) at 20 min. By changing the relative vapor pressure of phenylene ether vapor, the effect of relative solvent vapor pressure on the preparation of PVP film by solvent vapor assisted annealing was studied. With the increase of relative vapor pressure, the total thickness (less than 30 nm) and the thickness of rough layer of PVP film are all decreased, and the densification of the film is improved. The J-V characteristics of the MIS structure formed by this kind of film are measured. When the vapor pressure increases from 0.21 to 0.82, J decreases from 2.94 脳 10 ~ (-7) A / cm ~ (-2) to 4.2 脳 10 ~ (-8) A / cm ~ (2). The leakage mechanism is P-F effect when the electric field intensity is less than 1 MV / cm ~ (-1). Schottky emission is observed when the thickness of the film is greater than 1 MV / cm and the thin PVP film with a thickness of only 20 nm and a capacitance of 145n F / cm 2 can be obtained at the relative vapor pressure of 0.82.
【学位授予单位】：江南大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TN321.5

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