An ultra‐rigid close‐stacked piezo motor for harsh condition scanning probe microscopy

Abstract

We designed and produced a nearly closest packed stack motor with only one tiny gap of 0.15 mm in the middle of the stack. A low-voltage method of controlling the motor is introduced for the first time. Besides, the test results of the motor and the corresponding scanning tunneling microscope are also presented. To our surprise, it turns out to be so rigid that even running two oil pumps and one ultrasonic cleaner within 1 m range from a STM directly driven by this new motor cannot cause the STM to produce any visible difference in its the atomic resolution quality. This is a leap in building a true harsh condition atomic resolution SPM.

A compact, friction self-matching, non-inertial piezo motor with scanning capability

“…Piezoelectric motors (PMs) play a pivotal role in many cutting-edge scientific instruments, such as scanning probe microscopes [1][2][3][4][5], lithography machines [6][7][8], and DNA analyzers [9], because of their ability in nanoscale microscopic positioning precision and centimetre-level macroscopic stroke. Currently, the mainstream linear PMs are classified into inertial and non-inertial types [10], determined by the driving principle of the piezo actuator acting on the slide.…”

A High Rigidity and Precision Scanning Tunneling Microscope with Decoupled XY and Z Scans

“…It has been nearly 40 years since the first atomically resolved STM was formally invented by Binnig et al [6], and the major effort in building a high quality STM has been to improve the design of its head structure so as to obtain better stability, immunity to external vibration, and tip positioning precision, which are all vital to atomic resolution or tunneling current spectrum quality and are still far from being satisfactory even today, especially under harsh vibration and sound environments. To this end, in the past a few years since 2008, we had developed a number of new types of STM head structures that are suitable for working under harsh conditions, including the fully low voltage STM [7], SPM with an ultrarigid close-stacked piezo motor [8], and detachable scan unit [9] driven by new types of piezoelectric motors (GeckoDrive [10], PandaDrive [10], SpiderDrive [11], and TunaDrive [12, 13]), and finally obtained the world's first atomically resolved STM image in a water-cooled resistive magnet [14]. It was also the first atomic resolution image ever taken in a magnetic field exceeding the maximum magnetic field a superconducting magnet can generate.…”

Atomic resolution scanning tunneling microscope imaging up to 27 T in a water-cooled magnet

“…We have long been working on the development of harsh-condition STM and invented a series of high rigidity and compactness piezoelectric motors including the GeckoDrive, 19 TunaDriver, 20,21 PandaDrive 19 and SpiderDrive, 22 which are to some extent immune to external vibrations. [19][20][21][22][23][24] Based on these systematic studies, the major challenge of achieving atomic resolution in the WM's ultra-harsh conditions has been overcome and breakthrough has consequently been made. Room-temperature raw-data images of graphite with excellent quality atomic resolution were obtained in very high magnetic fields up to 27 T in a 32 mm bore water-cooled magnet, which has exceeded the maximum field of the conventional superconducting magnets.…”