Design Microelectromechanical Systems with Materials Once Thought Incompatible

This micro relay is only 32 mm<sup>3</sup> in volume.

It’s hard to believe that the phone in your pocket has more sensors than some World War 1 biplanes that flew in the sky.

We can thank microelectromechanical systems (MEMS) technology for the miniaturization of these components.

However, Sourabh Dhillon, business development manager at Integra Devices, an ANSYS Startup Program member, notes that many industrial components remain tricky to miniaturize using conventional MEMS technologies.

“MEMS manufacturers have miniaturized less than eight percent of an industrial component market that is over $200 billion in size,” clarifies Dhillon. “Material and process limitations of the semiconductor manufacturing process make these components hard to shrink.”

This is why Dhillon’s team worked so hard to develop the Amalga process. This new manufacturing technique builds small microdevices comprising materials that were once thought incompatible. Amalga opens the door for the miniaturization of many more electromechanical devices.

The Challenges of Manufacturing MEMS

“MEMs manufacturing through traditional semiconductor thin-film approaches are built like a skyscraper,” says Dhillon. “You build one layer on top of another until you have the 3D multilayer structure you need. This process can limit the layers you want to use.”

The materials used in electromagnetic components can’t always be made on a smaller scale, layer by layer.

Since each layer is made on top of the other, engineers need to ensure that the manufacturing process of the current layer won’t damage the layers below.

For example, think of a MEMS device with a polymer and ceramic layer. If the polymer layer comes before the ceramic one, then the heat needed to cure the ceramic would destroy the polymer.

How to Manufacture Each Layer of a Microelectromechanical Device Separately

Representation of the Amalga process.

Integra Devices’ Amalga process focuses on building each layer of the electromechanical device separately. These layers are then aligned and laminated together after each one has been created individually — like a wedding cake.

“Now the material limitations of building microelectromechanical devices are out the window,” says Dhillon. “They can be as thin or as thick as they need to be.”

The Amalga process will be big news for those creating microwave relays for the 5G, test and measurement markets.
Historically, there are two types of switches available, solid-state switches and larger electromechanical switches. MEMs switch development has attempted to combine the benefits of each, with limited success.

“MEMS developers have tried to miniaturize electromechanical switches for years, but the thin film approach makes this hard,” says Dhillon. “With the layers so thin and delicate, it is tough to get good contact and switch high power through it. Integra Devices is testing a switch that is similar in size to the solid-state switch with the high performance of a larger electromechanical switch.”

How Simulation Helps Design Microelectromechanical Devices

Structural simulation assesses the bonding of the dissimilar materials in a microelectromechanical device.

Simulation has a big part in the design of microelectromechanical devices.

Dhillon’s team uses the ANSYS platform to understand the mechanical, thermal and electrical implications of bonding layers of dissimilar materials together.

“In particular, ANSYS simulations are used to understand the stress, tolerance and performance of each layer and bonding material that goes into the Amalga process,” says Dhillon. “Simulation is also used to understand the electrical and mechanical performances of the devices. Finally, we use ANSYS to understand the effects of the environment on the device in order to design it for reliability.”

If you are an early stage company and interested in leveraging ANSYS simulation software to design your products, look into the ANSYS Startup Program.