Browse Prior Art Database

Ballistic Micro-Dispensing of Electronic Materials

IP.com Disclosure Number: IPCOM000117775D
Original Publication Date: 1996-Jun-01
Included in the Prior Art Database: 2005-Mar-31
Document File: 2 page(s) / 62K

Publishing Venue

IBM

Related People

Akin, JS: AUTHOR [+5]

Abstract

Disclosed is a method to improve the cycle time of dispensing electronic assembly materials. The method is to dispense material ballistically, instead of stopping at each dispense point.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 56% of the total text.

Ballistic Micro-Dispensing of Electronic Materials

      Disclosed is a method to improve the cycle time of dispensing
electronic assembly materials.  The method is to dispense material
ballistically, instead of stopping at each dispense point.

      When a series of dispense points lies along a line, the
location of each dispense point (1) is calculated by the controller
(2) in advance of the actual dispense action.  The dispenser (3) must
move in relation to the substrate (4), by either a head motion system
(5), or a table motion system, or both.  The motion system can move
in one, two, or three dimensions.  The Figure shows only a head
motion system in one dimension for simplicity.  The necessary axes of
motion are operated at a continuous velocity over the dispense
locations.  Each droplet (4) is dispensed prior to the target
location (1) appearing below the nozzle.  A ballistic calculation is
required to determine when to dispense each droplet.  In very simple
form, the equation to determine when to dispense is:
  xd = vt * (ts + h/vd)
  where,
  xd = distance before the target to begin the dispense sequence
  vt = fixed velocity of the motion
  ts = system delay time from initiating the drop command to drop
        formation
  h  = height of nozzle orifice above the substrate
  vd = velocity of the droplet downward

      By calculating xd in advance, the system controller can
determine when to dispense a droplet so that the target...