Hughes Aircraft Company

Palomar Technologies, Inc.

Palomar Products, Inc.

John B Gabaldon

Daniel D Evans, Jr

Dale W Cawelti

William H Hill

Todd G Wieseler

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 wire conveyance system is provided for a wire bonding machine having, in series, a first wire handler, a wire slacking device and a second wire handler. The wire slacking device includes a wire support chamber having a substantially enclosed bottom, opposing first and second vertical sidewalls, a substantially open top, a back opening and a front opening. The wire slacking device further includes a pressurized fluid source and first and second fluid orifices for receiving a pressurized fluid from the pressurized fluid source. The fluid orifices extend through the first or second sidewall of the wire support chamber with the second fluid orifice being positioned downstream of the first fluid orifice. First and second fluid paths are provided in fluid communication with the pressurized fluid source via the first and second fluid orifices. The first and second fluid paths extend upward between the first and second sidewalls of the wire support chamber and out the open top. A wire support path extends laterally through the wire support chamber above the first and second fluid orifices. The wire support path is substantially contactless with respect to the wire slacking device.

Wire conveyance system having a contactless wire slacking device

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

An automatic ultrasonic wire bonder employs a compliant motion servo (17, 119, 239, 200) on its Z axis drive to maintain a known, constant and steady force applied by the bonding tool (13) to the wire. The tool is resiliently mounted to a carriage (15) that is driven by a force control servo (17, 119, 238, 200). During bonding, the tool is pressed against the wire, and effects of variations in tool tip Z axis position caused by vibration, wire deformation during bonding and other factors of the equipment are minimized by a servo that precisely controls and maintains a fixed position of the carriage relative to the wire to thereby maintain a preselected force between the bonding tool tip and the wire.

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San Diego, CA, United States of America

John B Gabaldon