Browse Prior Art Database

Collet Pad Reference and Orientation Nest

IP.com Disclosure Number: IPCOM000041290D
Original Publication Date: 1984-Jan-01
Included in the Prior Art Database: 2005-Feb-02
Document File: 2 page(s) / 63K

Publishing Venue

IBM

Related People

Chirico, C: AUTHOR [+4]

Abstract

The Collet Pad Reference and Orientation Nest (PRON) (Figs. 1 and 2) allows a chip to be positioned positively without vibration. A desirable feature of the PRON is that it has a large capture range for a device (chip). This feature allows a great cost reduction in coarse locators, alignment tooling and time required to align the tool. As seen from Figs. 1 and 2, the PRON device nests the solder ball pattern, thereby locating the chip for subsequent placement. Fig. 3 illustrates the L-PRON concept for chip referencing. The vibrating mechanism is a piezoelectric material which is sandwiched between two metal plates and placed at an angle between two plastic pieces or metal pieces (Fig. 4). The bottom piece is connected to a mounting shaft. The top piece has the L-shaped stop.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 71% of the total text.

Page 1 of 2

Collet Pad Reference and Orientation Nest

The Collet Pad Reference and Orientation Nest (PRON) (Figs. 1 and 2) allows a chip to be positioned positively without vibration. A desirable feature of the PRON is that it has a large capture range for a device (chip). This feature allows a great cost reduction in coarse locators, alignment tooling and time required to align the tool. As seen from Figs. 1 and 2, the PRON device nests the solder ball pattern, thereby locating the chip for subsequent placement. Fig. 3 illustrates the L-PRON concept for chip referencing. The vibrating mechanism is a piezoelectric material which is sandwiched between two metal plates and placed at an angle between two plastic pieces or metal pieces (Fig. 4). The bottom piece is connected to a mounting shaft. The top piece has the L-shaped stop. When an electric field is applied to the plates, the piezoelectric material will flex proportional to the voltage applied. By changing the direction of the electric field (polarity of the voltage) the piezo will bend in the new direction. Therefore, if the voltage (electric field) were to vary at some frequency, the piezo will behave as a vibrator. If the amplitude of the voltage were to vary, the size of displacement by the piezo will vary proportionally. This can, therefore, vary the amplitude of vibration, if so desired. Since the bottom plate of the L-PRON is mounted to the host tool, the effective mass of that plate is very large in comparison to...