A MEMS guide plate for a high temperature testing of a wafer level packaged die wafer

Abstract

This paper describes the design and fabrication of a MEMS guide plate, which was used for a vertical probe card to test a wafer level packaged die wafer. The size of the fabricated MEMS guide plate was 10.6 9 10.6 cm. The MEMS guide plate consisted of 8,192 holes to insert pogo pins, and four holes for bolting between the guide plate and the housing. To insert pogo pins easily, an inclined plane was defined at the back of each hole. Pitch and diameter of the hole were 650 and 260 lm, respectively. In order to define inserting holes and inclined planes at an exact position, silicon MEMS technology was used such as anisotropic etching, deep reactive etching and more. Silicon was used as the material of the guide plate to reduce alignment mismatch between the pogo pins and solder bumps during a high temperature testing. A combined probe card with the fabricated MEMS guide plate showed good x-y alignment and planarity errors within ±9 and ±10 lm at room temperature, respectively. In addition, x-y alignment and planarity are ±20 and ±16 lm at 125°C, respectively. The proposed MEMS guide plate can be applied to a vertical probe card for burn-in testing of a wafer level packaged die wafer because the thermal expansion coefficient of the MEMS guide plate and die wafer is same.

Fabrication of a guide block for measuring a device with fine pitch area-arrayed solder bumps

“…6 (Choi and Ryu 2011). The substrate is a silicon on insulator (SOI) wafer consisting of a thickness of a 755 lm bottom silicon, a 1 lm thick buried oxide, and a 145 lm thick top silicon (Fig.…”

Highly Productive Process Technologies of Cantilever-type Microprobe Arrays for Wafer Level Chip Testing

“…The space transformer with microprobes is combined with the PCB, in order to measure the x-y alignment, planarity, leakage current, and contact resistance. These characteristics were measured with the probe card tester, PRVX2 [8,9]. The mechanical characteristics of conventional probe cards should be an x-y alignment of 8 μm or lower, and a planarity of 15 μm or lower [11].…”

“…probe tips, the vertical type, based on the array from standing probe tips vertically [4,5,8,9], and the MEMS type, which forms probe tips by using micromachining technologies [10][11][12][13]. Until now, conventional cantilever-type probe cards have frequently been used, which are fabricated manually.…”

“…The fabrication process for a cantilever-type MEMS probe card with its microprobes is shown in Figure 2 [8,9]. The substrate for the fabrication of the probes was a 6-inch, p-type, (100) silicon wafer, with thickness of 650 μm.…”

Two-Side Laser Processing Method for Producing High Aspect Ratio Microholes

“…arrays of micro holes with high aspect ratio (depth to diameter ratio), that are required for a range of applications in the electronics industry, i.e. interconnecting vias and printed circuit boards, and also for producing interface probe cards for 3D wafer bumps [7][8][9][10]. The target holes' diameters and pitches in such applications are less than 60 µm, whereas the holes' aspect ratios are higher than 5 with taper angle less than 10°.…”