Test Contactors

Semiconductor Test Contactors


Using state-of-the-art interconnect technologies, our sales and application engineers will work with you to provide the best Test Contactors solution to meet your requirement. We supply Test Contactors solutions for both your engineering & high volume production applications.

We will take your device mechanical drawing and use Solid Works modeling software to design a custom Test Contactors to be delivered within 3-4 weeks. M Specialties LLC designs Test Contactors for all types of packages including BGA, LGA, PoP, CSP, WLCSP, QFN, MLF, QFP, SOIC, TSOP, TSSOP and MEMS. We select the best contact solution for your application from a variety of different contact technologies including 50-Gig Pillar contacts, spring probes (spring pins), elastomer, electroformed component (EFC) contacts, advanced interposers, and others.

Our CNC milling machines have a positioning accuracy of 0.0002” and repeatability of position accuracy of +/- 0.0001” which allows us to supply Test Contactors for 0.35 mm pitch devices and lower.

All of our Contactors are designed to meet or exceed your electrical testing for applications of several MHz up to 50+GHz frequencies and challenging mechanical requirements. Our high quality contacts are capable of handling leaded and lead-free packaging materials, and with minimal cleaning, can handle in excess of 500K insertions in many cases. Whether your application is RF, high current, high power, low inductance, fine pitch, low resistance, or Kelvin, M Specialties LLC has a cost effective and reliable solution for your testing needs.

We use the latest plastic materials and each Test Contactors and lid part can be easily replaced on site by the customer or by one of our local support technicians. We provide full maintenance support services at our Arizona factory in a matter of days instead of weeks.

Our high mechanical advantage lids and low profile Test Contactors are designed to reach exceptional performance levels. All of our custom designs are modeled and approved by the customer before they are manufactured, allowing you to add or request specific features to be designed into the socket or lid to accommodate load board component placement or increased air flow to the top of the IC device.

Interconnect Technologies Used by M Specialties LLC

Wide selection of spring probes (spring pins) for <=0.35 mm pitch devices and above.

Spring pins with measured bandwidth for 37 GHz at -1dB.

Reliable pins with insertions >500K cycles in most cases.

Lead free solutions:

Increased yields

Less cleaning

Preserves PCB’s contact surface

Reduces cost of test

Conductive Elastomer for High speed lab testing available.

50-Gig Pillar.


M Specialties LLC Test Contactors can handle packages as small as 1 x 1 mm to upwards of 80 mm, and with pitches from <=0.35 mm to 1.27 mm and above. Most BGA Contactors use a floating plate design to position the device before contact with the spring probes, ensure continuity, and to act as a hard stop during test to protect the pins and the package. For smaller RF, QFN, and QFP style packages that require a shorter travel pin, we can utilize a 2 plate system that uses a shelf for aligning the package. We offer a variety of hand test lid options depending on the application and engineering needs. All lids are easily removed from the Test Contactors bases for a quick change from manual to handler and back.


  1. Standard Lid: Double-Clamping with spring loaded pressure block. Most commonly and best used on small devices (BGA, QFN, etc), QFP,TSSOP, Direct Attach, etc. Provides easy attachment and removal as well as automatic adjustment for package thickness variances.
  2. Linkage Style Lid: Provides better mechanical advantage than the Standard Lid and utilizes easy attachment and removal as well as a spring loaded pressure block for automatic adjustment. This can be used with Large BGA’s (up to about 40 mm), Small devices (BGA, QFN, etc.) but should be kept to relatively low force applications (~under 75 lbs (although exceptions can be made if footprint requires)). Not recommended for use with QFP or TSSOP.
  3. Z-Adjust Lid: Provides better mechanical advantage than Standard Lid (and somewhat better than the Linkage lid…but a lot better on larger devices) and can adjust for package thickness variance. Utilizes ergonomic handle that conforms to SEMI S8-1103 ergonomic guidelines. Directly attaches to contactors and provides best option for achieving continuity. Can be made to use for all devices, although not usually used for QFP’s or TSSOP’s (it still could be used for these, just that it would had considerable height to the full assembly.
  4. High Force, Low Friction, Z-Adjust, Ball-Bearing Lid: This design provides the best mechanical advantage for large devices with high pin counts. Utilizes a double ball-bearing design that results in low friction and optimal mechanical advantage when actuating large devices. Provides the best ergonomics when operating high force Test Contactors. Recommended for contactors with total forces above 80-90 lbs.

Lids 3 & 4 can made with an optional heat sink and/or Fan depending on the thermal requirements from the customer. And all lids are made with die probe access holes, sizes can vary based on the size of the lid and/or whether the customer wants to utilize a thermocouple in that same access hole.


Since 1999, we have been designing and manufacturing mechanical Test Contactors for our customers. We use the latest in contact technologies for engineering and final Test Contactors solutions. Our team of engineers is capable of producing a custom Test Contactors in 3-4 weeks standard lead time, with 2-3 week expedites available upon request.


Solidworks 3D modeling

Structural analysis

Thermal analysis


Engineering Capabilities

Surface mount and compression style contactors

High mechanical advantage lids.


Device pin spacing down to and below 0.35 mm pitch.

Utilization of high performance pins with 37 GHz bandwidth.

Experience with MDS-100, Tecapeek, Vespel, Torlon and a variety of other materials including ESD dissipative plastics.

Docking hardware & Seal plates.

Liquid cooling and thermal solutions.

We’re ready to start your project.