In this paper, study on the whole-domain coupling between electromechanical fields and charge carriers inside a piezoelectric PN junction is conducted in detail by abandoning the traditional depletion layer approximation and the low injection assumption. The barrier region of a PN junction has been fully opened in order that the upheaval change of electric field and carrier concentrations near the interface can be clearly exhibited and the evolution laws of potential barrier configuration with mechanical loadings can be thoroughly observed by taking into account the three basic motion modes of charge carriers (drift, diffusion and recombination). Effect of mechanical loadings on performance of piezoelectric PN junctions is further delineated from those changes induced by loadings, including the increment of electric field, the carrier redistribution modes and the disturbance laws of energy levels. It is found that the interface barrier configuration can only be significantly tuned by such a mechanical loading mode that the majority carriers are driven into the barrier region from the two sides to induce local carrier-inversion, while the carrier-inversion phenomenon is shown to be helpful for tuning the recombination rate of electrons and holes. As for the loaded configuration, the locations should be chosen according to that the mechanical loadings can cause the structure within an appropriate length near the PN interface into deformation to produce suitable tuning effect to the nearby barrier. Obviously, an effective mechanical tuning methodology on the potential barrier nature near a piezoelectric PN interface has been formed naturally. On this foundation, both the barrier configuration and the inner recombination rate of carriers can be expediently designed and controlled to realize the optimal conversion between electron current and hole current. Further analysis on a non-equilibrium piezoelectric PN junction subjected to a forward bias voltage shows the regulated mechanism of mechanical loadings on I–V characteristics of a piezoelectric PN junction as follows: the holes/electrons, passing through the PN interface from the p/n-zone into the n/p-zone in the form of majority-carrier current, enter into the recombination mode with the local electrons/holes, which induces the electrons/holes in the right/left sides to flow toward the central barrier region. Such a process indicates that the mutual conversion mechanism between two majority-carrier currents across the interface is just implemented by recombination of charge carriers near the barrier region. Thus, the regulation laws of mechanical loadings on the I–V characteristics of a piezoelectric PN junction are finally illustrated from tuning the potential barrier configuration near the interface and optimizing the recombination rate of electrons and holes in the barrier region. Obviously, study on this topic possesses referential significance to mechanical tuning the performance of piezoelectric PN junctions and piezotronic devices.

在本文中，通过放弃传统的耗尽层近似和低注入假设，详细研究了压电PN结内部的机电场与电荷载流子之间的全域耦合。PN结的势垒区域已完全打开，以便可以清楚显示界面附近电场和载流子浓度的剧变，并通过考虑以下因素，可以充分观察到势垒构型随机械载荷的演变规律。电荷载流子的三种基本运动模式（漂移，扩散和复合）。机械负载对压电PN结性能的影响从负载引起的那些变化（包括电场增量，载流子的再分配方式和能级的扰动律。已经发现，只有通过大多数载流子从两侧被驱动进入势垒区域以引起局部载流子反转，而载流子反转现象被证明是这样的机械加载模式，才可以显着地调整界面势垒结构。有助于调整电子和空穴的复合速率。对于负载配置，应根据机械负载可以使PN界面附近适当长度内的结构变形以对附近的屏障产生合适的调谐效果的位置来选择位置。显然，自然而然地形成了一种关于压电PN界面附近势垒性质的有效机械调谐方法。在此基础上 可以方便地设计和控制载流子的势垒结构和内部复合率，以实现电子电流和空穴电流之间的最佳转换。对正向偏置电压作用下的非平衡压电PN结的进一步分析表明，机械负载的调节机制压电PN结的I–V特性如下：空穴/电子以多数载流子的形式通过PN接口从p / n区进入n / p区，进入复合模式带有局部电子/空穴的电子，使右侧/左侧的电子/空穴流向中心势垒区。这样的过程表明跨接口的两个多数载流子电流之间的相互转换机制只是通过在势垒区附近重新组合载流子来实现的。因此，IV上机械载荷的调节规律最后，通过调整界面附近的势垒结构以及优化势垒区中电子与空穴的复合率，来说明压电PN结的特性。显然，对该主题的研究对于机械调整压电PN结和压电器件的性能具有参考意义。