Wafer level packaged cantilever array type contact force sensor

The wafer level packaged contact force sensor is presented for applications that require fine pitch measurement. The suggested cantilever array type sensor has high spatial resolution of 210 ¿m. To achieve reliable package, the sensor is capped by PDMS soft cap using wafer level molding and bonding process with 10 ¿m alignment precision. The resistance change over contact force was measured to verify the performance. The good linearity of the result confirms that the PDMS package transfers the forces appropriately. The measured sensitivity is about 4.5%/N.