1 2
PRINTER INK CARTRIDGE WITH DRIVE DeskJet 1200C Print Cartridge Platform" published in The
LOGIC INTEGRATED CIRCUIT Hewlett-Packard Journal dated February 1994.
In addition. Canon has incorporated the driver circuitry
BACKGROUND OF THE INVENTION and some control logic circuitry on the jet plate assembly in
1 Field of the Invention 5 their BubbleJet BJ_02 cartridge, which was developed for
'. „ ,„,,,. use with the BubbleJet printer. The jet plate assembly on the
The present invention relates generally to the field of BubbkJet cartrid is basica]1 m Mwm piate which
printer ink cartridges and, more specifically, to printer ink acts ag a hgat ^ a ^ boar4 and a ... substrate_ ^
cartridges which contain a portion of the dnve control logic sflicon comprises some Mya some logic
to operate the jet nozzles on the cartridge. 10 ... and the heat generating resistors. The heat gener
2. Description of the Related Technology ating resistors are encapsulated and form little cave-like
Ink cartridges are used in ink jet printers, a class of channels such that the ink is directed into the channels and
noncontact printers characterized by rapid heating and then ejected through the process of heating the ink and
expulsion of ink from nozzles onto paper. Many printer ink causing bubbles to eject the ink across the silicon substrate,
cartridges are passive devices, i.e., use passive components 15 Since the ink comes into contact with the silicon substrate,
on a jet plate assembly, such as resistors to heat the ink in the substrate must be protected by a barrier layer which is
the cartridge, to a point that it will expel from jet nozzles or not effected by the chemicals in the ink.
openings in the jet plate. As is known to those of skill in the art of silicon circuit
The resistors are formed utilizing thick or thin film fabrication, me larger me circuit that is produced on a silicon
technology on a substrate. Typically, one resistor per orifice 20 substrate, the harder the circuit is to manufacture. In
or jet is required. These passive printer ink cartridges are addition, as the size of the circuit increases, the yield of
"dumb" devices because they require an interface to control operable circuits that are produced decreases. Further, as the
and driver circuitry on the printer to determine when each circuit size increases, the potential for long term reliability
nozzle on the cartridge is to be fired. The printer sends problems increases. Therefore, the manufacturing costs rise
control signals to the resistors on the cartridge to control the 25 dramatically with the increased size of the circuit that is
firing sequence of the jets as the cartridge moves along the produced on silicon.
PaSe- In the case of developing a silicon integrated circuit on a
One of the first printer ink cartridges that used this passive jet plate to drive and control the operation of the jets, a
design was designed by Hewlett-Packard in approximately 3Q number of factors directly affect the size of the circuitry
1984 and was sold under the trade name ThinkJet Cartridge. required. Initially, each jet nozzle requires one heating
The ThinkJet Cartridge had 12 jet nozzles and required 13 element, such as a resistor, one drive control circuit and one
interconnect lines to the printer system to control the appli- or more control signals to indicate when the jet nozzle is to
cation of ink by the cartridge. The design and operation of be fired. As the number of jets increase, the size of the silicon
the ThinkJet cartridge is described in more detail in an 35 substrate required to house the driver circuits, control cir
article entitled, "History of ThinkJet Printhead cuits and the heating elements increases proportionally to
Development", published in The Hewlett-Packard Journal the number of added jets. Also, the increased number of jets,
dated May 1985. for example 84 jets, requires a silicon die having an ineffi
In approximately 1987, Hewlett-Packard developed the cient shape or having a large aspect ratio, i.e., a die having
DeskJet thermal printer inkjet cartridge which increased the 40 a l°ng length and a short width, because the increased
number of jets on the printer ink cartridge to fifty. However, number of jets causes the die to increase in length. Both
the Deskjet Cartridge is also a passive device that requires large dies and dies with a large aspect ratio are very difficult
an interface to control and driver circuits on the printer to t0 manufacture, further decreasing processes yields and
activate the jets. The DeskJet cartridge has fifty jets and increasing production costs.
requires fifty-six interconnect lines to the printer system to 45 In addition to the problems of silicon yield for such large control the application of ink by the cartridge. The design circuits, the circuitry on the jet plate must be able to and operation of the original DeskJet cartridge is described withstand the heat generated by the resistors as well as in more detail in an article entitled, "Low Cost Plain Paper problems associated with silicon coming into constant conPrinting," published in The Hewlett-Packard Journal dated tact with moving heated ink. Therefore, the production of the August 1992. 50 silicon integrated circuit on the jet plate must include Recently. Hewlett-Packard designed a thermal printer ink additional steps to prevent long-term degradation of the cartridge, Part No. HP51640, used in a DeskJet 1200 printer silicon due to contact with the chemicals in the ink, to also by Hewlett-Packard which incorporated a portion of the cavitation problems caused by the moving ink, etc. These driver electronics and some control logic onto the jet plate processes increase the production costs for making a jet of the printer ink cartridge. In this particular case, the jet 55 plate- These same processes may also decrease the perforplate is composed of the following structures: (1) a silicon mance characteristics of the driver and logic circuits on the substrate which houses the driver control circuitry for each Jet plate.
fUS\"°T T*** « ... ... j 1* SUMMARY OF THE INVENTION to be fired, and (3) the heat generating resistors. Since the
driver control circuitry and the control logic circuitry is 60 A printer ink cartridge of the preferred embodiment
proximate to the heat generating resistors, the driver control provides some control and driver circuitry on the printer ink
logic circuitry is susceptible to the heat generated by the heat cartridge without adding complexities to the manufacture of
generating resistors. The jet plate is located proximate to the the jet plate assembly and without decreasing the perfor
jet nozzles to heat the ink for expulsion. The design and mance characteristics of the driver and logic circuitry. The
operation of the DeskJet 1200 cartridge is described in more 65 control and driver circuit is attached to the cartridge body
detail in two articles entitled, "The Third-Generation HP spaced apart from a jet plate, and electrical conductors
Thermal InkJet Printhead" and Development of the "HP connect the jet plate to the control and driver circuit. The
