Hughes Aircraft Company

Palomar Technologies, Inc.

Palomar Products, Inc.

Daniel D Evans, Jr

John B Gabaldon

Dale W Cawelti

William H Hill

James D O'Bryan, Jr

A process control procedure for a bonding process includes predetermining a deformation limit and a deforming time limit is for deforming a bonding precursor member. The bonding precursor member is deformed while monitoring instantaneous deformation values and instantaneous deforming time values for the bonding precursor member. A deforming shut-down time value is set at an instantaneous deforming time value corresponding to an occurrence of a first condition or a second condition. The first condition is an instantaneous deformation value for the bonding precursor member reaching the deformation limit and the second condition is an instantaneous deforming time value for the bonding precursor member reaching the deforming time limit. Deformation of the bonding precursor member is shut down at the deforming shut-down time value, thereby producing a deformed bond member from the bonding precursor member.

Monitoring deformation and time to logically constrain a bonding process

A bond head is provided for a wire bonding machine having a linear axis frame, a rotary axis frame, a bond tool and a wire clamp. The linear axis frame is vertically linearly displacable along a linear axis, while the rotary axis frame is rotationally displacable along a rotary axis. A pivotal connector is provided which pivotally connects the rotary axis frame to the linear axis frame, enabling the rotary axis frame to rotate independent of linear displacement of the linear axis frame. The bond tool is connected to the rotary axis frame and is vertically linearly displacable in response to vertical linear displacement of the linear axis frame and rotationally displacable in response to rotational displacement of the rotary axis frame. The wire clamp is connected to the linear axis frame and is vertically linearly displacable in response to vertical linear displacement of the linear axis frame, while the wire clamp is maintained rotationally stationary during rotational displacement of the rotary axis frame. The bond head also includes a linear motion assembly and a rotary motion assembly. The linear motion assembly has a linear driver, a linear position detector and a linear driver controller. The rotary motion assembly correspondingly has a rotary driver, a rotary position detector and a rotary driver controller.

Bond head having dual axes of motion

A method of bond quality monitoring wherein a bonding machine is fitted with a touchdown mechanism including a pair of contacts (23, 24), which normally open upon touchdown of a bonding tool (27) raised and lowered by a bond head carriage (13). As the tool (27) is lowered towards a bonding surface (31), the bonding machine's computer (61) performs a test (103) to sense production of a touchdown signal produced by opening of the contacts (23, 24). If touchdown is sensed, the carriage (13) proceeds to an overtravel position. Upon reaching the overtravel position, a second test (108) is performed to confirm touchdown, and energy is then applied to the bond site. During energy application, the logic state of the touchdown mechanism is checked to ensure that the contacts do not close, for example, to check for application of inadequate force during bonding. If a contact closure is sensed, the bond site location is logged for further examination such as a nondestructive pull test. When the carriage ascends, the distance it travels before closure of the contacts ( 23, 24) is used as a measure of bond deformation and, hence, bond quality.

Electrical interconnect integrity measuring method

A method of bond quality monitoring wherein a bonding machine is fitted with a touchdown mechanism including a pair of contacts (23, 24), which normally open upon touchdown of a bonding tool (27) raised and lowered by a bond head carriage (13). As the tool (27) is lowered towards a bonding surface (31), the bonding machine's computer (61) performs a test (103) to sense production of a touchdown signal produced by opening of the contacts (23, 24). If touchdown is sensed, the carriage (13) proceeds to an overtravel position. Upon reaching the overtravel position, a second test (108) is performed to confirm touchdown, and energy is then applied to the bond site. During energy application, the logic state of the touchdown mechanism is checked to ensure that the contacts do not close for example to check for application of inadequate force during bonding. If a contact closure is sensed, the bond site location is logged for further examination such as a nondestructive pull test. When the carriage ascends, the distance it travels before closure of the contacts ( 23, 24) is used as a measure of bond deformation and, hence, bond quality.

In a system wherein a system master (11) communicates with a plurality of subsystems (13, 25, 27, 29), each subsystem (13, 25, 27, 29) is associated with a unique reset address and a reset circuit which recognizes that reset address and generates a reset signal. Each reset circuit includes an address decoder (15) for decoding the reset address to produce a signal which closes a logic gate switch (19). The logic gate switch (19) is repeatedly closed in response to repeated assertions of the address to successively discharge the voltage on a capacitor (C). When the capacitor voltage is discharged to a selected level, a buffer level detector circuit (23) generates the reset signal.

Computer subsystem reset by address dependent RC discharge

Apparatus and method for detecting missing interconnect material. The distance traveled by a bonding tool is measured while the interconnect material is being bonded to a site. Unless it exceeds a predetermined threshold, a signal is generated indicating missing interconnect material. A pivoting system associated mating electrical contacts, and a measurement/comparator are advantageously employed to facilitate this measurement.

Apparatus and method for detecting missing interconnect material

In bonding a number of pads which may have different heights within a predetermined tolerance the bonding tool (28, 24, 14, 10) is moved in slow speed search mode (70) to contact the first pad (P.sub.1) and store the height (H.sub.1) of the first pad (P.sub.1). After a predetermined amount of continued overtravel (OT.sub.1) the bond is performed and the tool raised. Operations on other pads may occur at this point. The tool is then moved to a point above the location of the second pad. The tool is moved down to the second pad without a search mode but to a second pad target height (H.sub.1 +OT.sub.2) that is the sum of the sensed height of the preceding pad and an overtravel distance. The approach of the tool to the second pad is done at high speed (84,88) and senses and stores the point of contact, or the actual sensed height of the second pad, for use in determining a target height for the high speed approach to the next pad, thereby eliminating the slow speed search required for all pads but the first on a part.

Method for reducing time to place a tool onto a workpiece

A system bus (13) carrying multidimensional path data interfaces with a plurality of local microprocessors (24), one for each dimension, through a plurality of dual access memory structures (21), one for each local microprocessor (24). A local arbiter (35) controls access to each dual access memory structure (21), facilitating elimination of wait states in data transfers between the bus (13) and memory (21) and between the local microprocessor (24) and memory (21). The arbiter (35) is implemented using a programmable logic device state machine approach, which implements a mode of operation wherein the circuitry is armed for a transfer between a local microprocessor (24) and the dual access memory (21) and accomplishes such transfer with no wait states. The state machines and dual access memory (21) are driven by a clock which is twice as fast as that driving the local microprocessor (24) and the state machine implementation utilizes this fact to insure memory access to both the system bus (13), and the local microprocessor (24) with priority going to the local microprocessor (24).

High speed digital motion controller architecture

A digital robotic axis controller which employs a digital processor to apply the inverse of a plant model transfer function to positional information representative of a target path to generate a feed forward position control signal and to combine an error signal with the positional information to generate a feedback control signal. The feed forward and feedback control signals are combined to produce a total position control signal which is supplied to a digital-to-analog converter and then to a plant comprising an amplifier, a motor for establishing the actual position of a robotic member, and an encoder for deriving the error signal from the motor position. In application, a number of such plants are controlled to achieve a coordinated multidimensional movement with increased accuracy.

Robot axis controller employing feedback and open loop (feedforward)

A digital servo system for causing a mechanical element (48) to track a desired path and hold various positions along the path and employing a lead/lag integrator (18) in parallel with a feedback control loop. The input to the integrator (18) is switched between velocity (V.sub.EK) error during pathtracking and position error (E.sub.K) during holding to increase the resistance of the mechanical element (48) to position changes caused by outside forces during both pathtracking and holding. The integrator function employed uses a term (U.sub.integrator(k-1)) representing a previous integrator output value to assist in smoothing perturbations caused by switching between position and velocity error.

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Oceanside, CA, United States of America

Daniel D Evans, Jr