Method for Fabrication of Micro-Holes on Metal or Non-Metal Non-Planar Surfaces

Life Sciences : Drug Delivery

Available for licensing


  • Salomon Stavchansky, Ph.D. , Pharmaceutics
  • Phillip Bowman, Ph.D. , Pharmaceutics
  • Paul Ho, Ph.D. , Mechanical Engineering
  • Zhiquan Luo , Physics
  • Zhuojie Wu , Physics
  • Ashish Rastogi , Pharmaceutics

Background/unmet need

The technologies to fabricate micro-structures on planar silicon wafers are well developed. However, it is difficult to fabricate on non-planar substrate, such as a cylindrical polymer tube. The current method to fabricate micro-holes on a cylindrical tube is usually performed by laser blazing. Laser blazing is a serial process which is time-consuming and difficult to adopt for mass production. The micro-holes fabricated by laser blazing normally have diameters larger than 15 microns, and it is difficult to control the shape and depth of the micro-hole. In addition, the laser beam usually burns and damages the material around micro-holes, which is not desirable for many medical applications.

Invention Description

Researchers at The University of Texas at Austin have developed a process for fabrication of micro-holes on non-planar surfaces. The micro-hole can be formed on a wide range of substrates, metal or non-metal, and shapes, such as tubes, depending on the application. The micro-hole varies in size from a fraction of a micron to hundreds of microns in diameter and can have a variety of shapes. The fabrication process is based on photolithography and reactive ion etching technologies.

Devices containing the micro-holes can be used for a wide range of medical and biomaterials applications, including the use for medical implantation and controlled drug delivery. This technology can be used to fabricate circular holes on polyimide tubes to develop drug delivery devices. The same process can be used to fabricate MEMS structure and sensors for other applications.


  • Offers a parallel process
  • Suitable for mass production
  • Lower cost
  • Greatly improves the capabilities and control in producing holes of non-circular shapes and varying sizes
  • Can be integrated with MEMS and sensors to form devices for a range of applications, including microelectronics, medical delivery, and biomaterials


  • Special structures fabricated on silicon wafer to hole the polymer tubes
  • Standard microelectronic technologies used

Market potential/applications

Pharmaceutical and biotechnology companies interested in manufacturing micro-holes, such as for the application of drug delivery devices.

Development Stage

Proof of concept