MEMS Pressure Sensor Technology

Krystal Bond™ Technology is a new MEMS technology for pressure sensing. It is an advanced process in which inorganic materials are molecularly diffused onto a metallic surface in the presence of certain gases. A diffusion takes place at a sufficiently high temperature that is far below the melting point of the metal. As the process occurs, the bonding material flows while assuring that the high yield strength properties of the metal are preserved. As the temperature is reduced, the bonding material solidifies and secures the silicon strain gauge in position.

This process provides a high electrical isolation with low leakage rates at 500VAC, making this technology ideal for process control applications. Operating at low strain levels, AST’s specially grown and micro-machined silicon strain gauges yield a high output with low thermal errors. This technology uses a sensing element machined from one piece of stainless steel. This is unique and new to pressure sensing because competing technologies use a welded diaphragm, a welded oil-filled cavity, or a ceramic diaphragm held by an O-ring. By designing the pressure sensor cell with one piece of material, AST has eliminated weak points and contamination risks.

With seventy-five percent less operating strain of the diaphragm in comparison to the competition, the AST pressure sensor cell has less fatigue, higher proof and burst pressure capability, and excellent long term stability. By using inorganic materials in the process bonding the strain gages to the diaphragm, there is no shelf life to the pressure sensing element.

Krystal Bond™ Technology can be used on a variety of materials including 17-4PH, 316L, Inconel718, and Titanium and designed in different package sizes to meet customer demands. From sour gas in the oil patch to medical pumps in the human body, our MEMS technology can be matched to a variety of media requirements.

- Karmjit S. Sidhu
Vice President Sales & Marketing