Although Pb-based perovskite solar cells already achieve power conversion efficiencies (PCE) beyond 20 %, the use of toxic Pb is causing considerable environmental concern. As a consequence, a variety of alternative cations have been investigated to replace Pb 2+ in the perovskite structure. Methylammonium bismuth iodide (MA 3 Bi 2 I 9 , MBI) has shown promising results for environmentally benign and chemically stable devices. While the PCE of MBIbased solar cells are still comparably low, structural improvements have been made by using chemical vapor deposition (CVD). CVD allows for the well-controlled formation of coherent and dense MBI layers in contrast to solution-processing. In this work, CVD as a possible MBI fabrication method for efficient and size-scalable solar cells is discussed. The precursors MA iodide (MAI) and Bi iodide (BiI 3 ) are deposited in an alternating deposition process forming the desired MBI perovskite on the heated substrate. Substrate temperatures as well as deposition times of each precursor are varied with the aim of forming coherent and dense MBI layers. Optimized films are further processed to solar cell prototypes and compared with solution-processed reference devices. The results reveal that CVD possesses great potential to enable the manufacture of MBI photovoltaic (PV) devices processed in a solvent-free environment.

Purpose Since 2019, intraoperative networking with ISO IEEE 11073 SDC has, for the first time, enabled standardized multi-vendor data exchange between medical devices. For seamless plug-and-play integration of devices without previous configuration, further specifications for device profiles (“device specializations”) on top of the existing core standards must be developed. These generic interfaces are then incorporated into the standardization process. Methods An existing classification scheme of robotic assistance functions is being adopted and used as a baseline to derive functional requirements for a universal interface for modular robot arms. Additionally, the robot system requires machine-machine interfaces (MMI) to a surgical navigation system and a surgical planning software in order to carry out its function. Further technical requirements are derived from these MMI. The functional and technical requirements motivate the design of an SDC-compatible device profile. The device profile is then assessed for feasibility. Results We present a new modeling of a device profile for surgical robotic arms intended for neurosurgery and orthopedic surgery. The modeling in SDC succeeds for the most part. However, some details of the proposed model cannot yet be realized within the framework of the existing SDC standards. Some aspects can already be realized, but could be better supported in the future by the nomenclature system. These improvements are being presented as well. Conclusion The proposed device profile presents a first step toward a uniform technical description model for modular surgical robot systems. The current SDC core standards lack some functionality to fully support the proposed device profile. These could be defined in future work and then included in standardization efforts.

Surgical procedures require a variety of medical devices, each bearing an ever-increasing number of settings and functions. Most devices are placed in the unsterile area of the operating room. Therefore, the surgeon and other sterile staff members are not able to interact with the device interfaces. Surgeons often rely on so-called ‘yell-and-click communication’ to have a setting changed, which is error-prone, slow and moreover leads to process interruptions for the involved OR personnel. Suitable control devices, like a foot switch or a sterile user interface, can allow sterile staff members direct access to certain device functions. In a networked operating room, such control devices could exist for any controllable value or operation. Due to spatial limitations in the OR, it is desired to use as few physical control devices as possible. To control a large variety of parameters, these control devices' associated functionality could be re-assigned during a surgical procedure. The manufacturer-independent communication standard ISO IEEE 11073 SDC is tailored for medical device control in the operating room and makes such a re-assignable control interface technically feasible.However, each control association must be assessed with regard to its usability and risk management. For example, a critical control target must never be controlled by an element which is too coarse for the intended task. Therefore, it is a key requirement to develop a software model for control devices and a mechanism to allow or deny a proposed mapping desired by the user based on safety and usability criteria.In the present work, we outline a system to describe and categorize input devices (control elements such as buttons, knobs and foot switches) and controllable counterparts (Targets) typically found in the surgical context. Great attention is given to the means necessary to safely control critical parameters. We assess the current descriptive capabilities of SDC and propose necessary additions to create more comprehensible software models of the control devices. Finally, we present a new convention for medical device modeling which could be used to propose or prohibit unsafe or unintended mappings in a user interface for configuring control devices in the operating room.