Patent Publication Number: US-6992862-B2

Title: Disk drive with controlled pitch static attitude of sliders on integrated lead suspensions by improved plastic deformation processing

Description:
This patent application is related to U.S. patent application Ser. No. 10/651,262, entitled, Method of Controlling Pitch Static Attitude of Sliders on Integrated Lead Suspensions by Improved Plastic Deformation Processing, which was filed concurrently with the present patent application. 
     BACKGROUND OF THE INVENTION 
     1. Technical Field 
     The present invention relates in general to head gimbal assemblies for data recording disk drives and, in particular, to an improved hard disk drive with controlled pitch static attitude of the sliders on integrated lead suspensions in head gimbal assemblies by a manufacturing process. 
     2. Description of the Related Art 
     Generally, a data access and storage system consists of one or more storage devices that store data on magnetic or optical storage media. For example, a magnetic storage device is known as a direct access storage device (DASD) or a hard disk drive (HDD) and includes one or more disks and a disk controller to manage local operations concerning the disks. The hard disks themselves are usually made of aluminum alloy or a mixture of glass and ceramic, and are covered with a magnetic coating. Typically, one to six disks are stacked vertically on a common spindle that is turned by a disk drive motor at several thousand revolutions per minute (rpm). 
     A typical HDD also utilizes an actuator assembly. The actuator moves magnetic read/write heads to the desired location on the rotating disk so as to write information to or read data from that location having an air bearing surface (ABS) that enables the slider to fly at a constant height close to the disk during operation of the disk drive, by a cushion of air generated by the rotating disk. Within most HDDs, the magnetic read/write head transducer is mounted on a slider. A slider generally serves to mechanically support the head and any electrical connections between the head and the rest of the disk drive system. The slider is aerodynamically shaped to glide over moving air in order to maintain a uniform distance from the surface of the rotating disk, thereby preventing the head from undesirably contacting the disk. Each slider is attached to the free end of a suspension that in turn is cantilevered from the rigid arm of an actuator. Several semi-rigid arms may be combined to form a single movable unit having either a linear bearing or a rotary pivotal bearing system. 
     The head and arm assembly is linearly or pivotally moved utilizing a magnet/coil structure that is often called a voice coil motor (VCM). The stator of a VCM is mounted to a base plate or casting on which the spindle is also mounted. The base casting with its spindle, actuator VCM, and internal filtration system is then enclosed with a cover and seal assembly to ensure that no contaminants can enter and adversely affect the reliability of the slider flying over the disk. When current is fed to the motor, the VCM develops force or torque that is substantially proportional to the applied current. The arm acceleration is therefore substantially proportional to the magnitude of the current. As the read/write head approaches a desired track, a reverse polarity signal is applied to the actuator, causing the signal to act as a brake, and ideally causing the read/write head to stop and settle directly over the desired track. 
     The suspension of a conventional disk drive typically includes a relatively stiff load beam with a mount plate at the base end, which subsequently attaches to the actuator arm, and whose free end mounts a flexure that carries the slider and its read/write head transducer. Disposed between the mount plate and the functional end of the load beam is a ‘hinge’ that is compliant in the vertical bending direction (normal to the disk surface). The hinge enables the load beam to suspend and load the slider and the read/write head toward the spinning disk surface. It is then the job of the flexure to provide gimbaled support for the slider so that the read/write head can pitch and roll in order to adjust its orientation for unavoidable disk surface run out or flatness variations. 
     The flexure in an integrated lead suspension is generally made out of a laminated multi-layer material. Typically, it consists of a conductor layer (like copper), a di-electric layer (like polyimide), and a support layer (like stainless steel). The electrical lead lines are etched into the conductor layer, while the polyimide layer serves as the insulator from the underlying steel support layer. The steel support layer is also patterned to provide strength and gimbaling characteristics to the flexure. The conducting leads, called traces, which electrically connect the head transducer to the read/write electronics, are often routed on both sides of the suspension, especially in the gimbal region. Normally the traces consist of copper conductor with polyimide dielectric layer but no support stainless steel layer and only provide the electrical function. The mechanical function is provided by the flexure legs (stainless steel only), which normally run adjacent to the traces. 
     The static attitude of the slider is defined by the angular position of the slider ABS with respect to the mounting platform and is specified by design in conjunction with a specific ABS, so that the slider can maintain an optimal flying height for the transducer thereon to read and/or write data on to the recording surface of the disk. To counter the airlift pressure exerted on the slider during disk drive operation, a pre-determined load is applied through a load point on the suspension to a precise load point on the slider. The slider flies above the disk at a height established by the equilibrium of the load on the load point and the lift force of the air bearing. The load of the suspension together with static attitude, control and maintain the optimal flying height of the slider. 
     The pitch static attitude in a suspension is produced to a desired value by forming the flexure legs, and then making mechanical/thermal adjustments. Since, the traces are an integral part of the flexure in an integrated lead suspension, joined to the flexure legs near the transducer bonding area in the front and near the back (leading edge) of the slider in the back, the traces provide resistance to the deformation of flexure leg and deflection of flexure tongue by an opposing force. Hence a significantly higher force is needed to plastically deform the flexure legs to obtain a desired pitch angle that also includes the overcoming the opposite forces produced by the traces. This process leaves residual stresses in the traces and the traces do not remain in the same plane as that of the rest of the flexure. One way to confirm the existence of stress in the traces is to cut the traces or subject the suspension to thermal processes. The stress is relieved by either process and as a result the pitch angle is increased. 
     This is an inherent problem of the integrated lead suspension. Once the suspension is manufactured by the supplier with formed flexure legs and adjustment to achieve desired pitch angle, it comes with variable amount of stress in the conductive traces. A part or all of the stress is likely to be relieved if and when the said suspension is subjected to a thermal process, thereby changing the pitch static attitude of the suspension or head gimbal assembly. 
     To successfully achieve file performance, the read/write head must fly steadily at a given fly height over the disk with minimal variations. Since the variations in fly height are dependent on the various sensitivities of the fly height to the process parameters as well as the variability of the parameters, a state-of-the-art air bearing surface (ABS) design and tight process control are mandatory to minimize such variations. Pitch static attitude and variations significantly affect the fly height. Moreover, a very low or negative pitch static attitude can cause disk damage and a very high pitch angle can promote a bi-stable behavior in fly height. 
     Thus, an improved hard disk drive having controlled process parameters, such as pitch static attitude, of the sliders on integrated lead suspensions in head gimbal assemblies is needed. 
     SUMMARY OF THE INVENTION 
     The present invention is directed to an improvement in hard drives during the manufacturing of the integrated lead suspensions, which overcomes the disadvantages and limitations in the prior art described above. 
     The integrated lead suspension is a multi-layer assembly having a load beam, a mount plate, a hinge and a flexure. The flexure is made out of a multi layer structure consisting of a support layer, a dielectric layer, and an electrically conductive layer. The flexure has a gimbal area with a flexure tongue to which a slider is attached. The electrically conductive layer is etched to form conductive leads or traces interconnecting the head transducer to the read/write electronics. The traces run parallel to the flexure legs made out of the support layer stainless steel in the gimbal area. 
     In one embodiment of the present invention, the flexure legs and traces are simultaneously plastically deformed to eliminate residual stresses in the traces during the manufacturing of the integrated lead suspension. The flexure legs and the outrigger leads are deformed at approximately the same longitudinal location. The deforming may comprise, for example, simultaneously creasing both the flexure legs and the outrigger leads with a roller, or simultaneously step-forming both the flexure legs and the outrigger leads. In addition, the outrigger leads may be protected from mechanical damage, such as scratching, during the plastic deformation. 
     In another embodiment of an integrated lead suspension includes a slider that is electrically interconnected with outrigger leads on the suspension by solder ball bonding. Solder ball bonding requires significantly high temperatures to reflow the solder balls. When such temperatures are applied to the suspension during the head gimbal assembly process, the pitch static attitude of the slider can go out of control as the excess heat from solder ball bonding flows through the conductors of outrigger leads. Solder ball bonding thereby thermally affects the residual stress level in the outrigger leads and, thus, affects the pitch static attitude of the slider. A similar situation can also arise if the integrated lead suspension or the head gimbal assembly made of an integrated lead suspension is subjected to other thermal processes. 
     To overcome this problem, both the flexure legs and the outrigger leads are simultaneously plastically deformed during the manufacturing of the integrated lead suspension, to permanently define a stable pitch static attitude before solder ball bonding. The flexure legs and the outrigger leads are deformed at approximately the same longitudinal location. The deforming step may comprise, for example, simultaneously creasing both the flexure legs and the outrigger leads with a roller, or simultaneously step-forming both the flexure legs and the outrigger leads. In addition, the outrigger leads are protected from mechanical damage, such as scratching, during the plastic deformation. 
     The foregoing and other objects and advantages of the present invention will be apparent to those skilled in the art, in view of the following detailed description of the preferred embodiment of the present invention, taken in conjunction with the appended claims and the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       So that the manner in which the features and advantages of the invention, as well as others which will become apparent, are attained and can be understood in more detail, more particular description of the invention briefly summarized above may be had by reference to the embodiment thereof which is illustrated in the appended drawings, which drawings form a part of this specification. It is to be noted, however, that the drawings illustrate only an embodiment of the invention and therefore are not to be considered limiting of its scope as the invention may admit to other equally effective embodiments. 
         FIG. 1  is a schematic top plan view of one embodiment of a hard disk drive. 
         FIG. 2   a  is a top plan view of an integrated lead suspension utilized by the disk drive of  FIG. 1 . 
         FIG. 2   b  is a perspective view of the head gimbal assembly using the integrated lead suspension of  FIG. 2   a.    
         FIGS. 3   a  and  3   b  are top plan and side views, respectively, of the head gimbal assembly of  FIG. 2   b.    
         FIG. 4  is a top plan view of a distal portion of an integrated lead suspension. 
         FIG. 5  is an enlarged side elevational view of a distal portion of the head gimbal assembly of  FIG. 4 . 
         FIG. 6  is a top plan view of the distal portion of the integrated lead suspension of  FIG. 5 . 
         FIG. 7  is a side view of the integrated lead suspension during the deformation process. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring to  FIG. 1 , a schematic drawing of one embodiment of an information storage system comprising a magnetic hard disk file or drive  111  for a computer system is shown. Drive  111  has an outer housing or base  113  containing a plurality of stacked, parallel magnetic disks  115  (one shown) which are closely spaced apart. Disks  115  are rotated by a spindle motor assembly having a central drive hub  117 . An actuator  121  comprises a plurality of parallel actuator arms  125  (one shown) in the form of a comb that is pivotally mounted to base  113  about a pivot assembly  123 . A controller  119  is also mounted to base  113  for selectively moving the comb of arms  125  relative to disks  115 . 
     In the embodiment shown, each arm  125  has extending from it at least one cantilevered integrated lead suspension  127 . A magnetic read/write transducer or head is mounted on a slider  129  and the slider is attached to the end of the integrated lead suspension  127 . The read/write heads magnetically read data from and/or magnetically write data to disks  115 . The level of integration called the head gimbal assembly  130  is the head and the slider  129 , which are mounted on integrated lead suspension  127 . The slider  129  is usually bonded to the end of integrated lead suspension  127 . In the embodiment shown, the head may be pico size (approximately 1250×1000×300 microns) and formed from ceramic or intermetallic materials. The head also may be nano size (approximately 2050×1600×450 microns), or femto size (approximately 850×700×230 microns). The slider  129  is pre-loaded against the surface of disk  115  (preferably in the range one to four grams) by integrated lead suspension  127 . 
     Integrated lead suspensions  127  have a spring-like quality, which biases or urges the air bearing surface of slider  129  against the disk  115  to enable the creation of the air bearing film between the slider  129  and the surface of disk  115 . A voice coil  133  housed within a conventional voice coil motor magnet assembly  134  (top pole not shown) is also mounted to arms  125  opposite the head gimbal assemblies. Movement of the actuator  121  (indicated by arrow  135 ) by controller  119  moves the sliders  129  of the head gimbal assemblies radially across tracks on the disks  115  until the heads settle on the target tracks. The head gimbal assemblies operate in a conventional manner and always move in unison with one another, unless drive  111  uses multiple independent actuators (not shown) wherein the arms  125  can move independently of one another. 
       FIGS. 2–4  show various views and details of the head gimbal assembly  130  and the integrated lead suspension  127  for a better understanding of the problem and the present invention. Such an integrated lead suspension  127  comprises a load beam  155 , to which is welded a flexure assembly  163 . The flexure assembly is generally an elongated structure that is aligned with the load beam  155 . The flexure assembly comprises a support layer  174  such as stainless steel, a dielectric layer  175  such as polyimide, and a conductive layer such as copper from which a set of electrical traces  173  have been patterned by etching. The integrated lead suspension  127 , also has a hinge  159  and mount plate or base plate  157  welded to the back end which is swaged to the actuator arm  125  during head stack assembly operation. 
       FIG. 3A  is a top plan view and  FIG. 3B  shows a side cross-sectional view of the head gimbal assembly  130 , as shown in  FIG. 2 . The pitch static attitude of a slider in a head gimbal assembly is defined as the angle between the plane of the slider air bearing surface (ABS)  140  and the plane of the mounting surface of the mount plate  157 , when the center of the ABS is at the design specific “offset” height (illustrated in  FIG. 3B ). 
       FIG. 4  is a top plan view of the gimbal area of the integrated lead suspension  127 . As described earlier, the flexure is made out of a multilayer laminate structure having a support layer  174 , a dielectric layer  175  and a conductive layer that has been patterned to provide traces  173  to interconnect the head transducer to the read/write electronics. Two flexure legs  165  of support layer stainless steel connect the main body of the flexure to the flexure tongue  169  to which a slider is attached to form a head gimbal assembly. It can be seen from  FIG. 4  that the conductive traces  173 , on either side of the flexure assembly, run reasonably parallel to the flexure legs  165 , except where they are connected to each other in areas  181 ,  182  towards the back of the flexure tongue and areas  183 ,  184  towards the front side of the flexure tongue. It is also clear that the conductive traces  173  do not have the support layer stainless steel between areas  181 – 182  and  183 – 184 . The conductive traces  173  terminate at pads  185  to which the head pads in the slider are connected by various methods. In some cases, the dielectric layer  175  is made by a 3-layer structure; a core layer of Kapton with thin layers of thermo plastic polyimide on either side. The thermo plastic polyimide (TPI) layer has a glass transition temperature (Tg) close to 200 deg C. and helps in bonding of the core Kapton layer to stainless steel base layer  174  on one side and the conductive copper layer on the other side. 
     The pitch static attitude of an integrated lead suspension assembly is defined similar to that of the head gimbal assembly ( FIG. 3   b ), as the angle between the plane of the flexure tongue and the plane of mounting area of the mount plate, with the center of the flexure tongue at a specified “offset” height, different from that of head gimbal assembly by the thickness of the slider. In an integrated lead suspension, the desired pitch static attitude is normally achieved by plastically deforming the flexure legs  165  during the manufacturing of the integrated lead suspension so that the flexure tongue is rotated. The degree of deformation needed depends on the magnitude of pitch static attitude required by design. 
     Since the flexure legs and traces are connected as described earlier, the traces adjacent to the flexure legs are in a state of stress when the flexure legs are plastically deformed. The deformation of the flexure leg tries to rotate the flexure tongue in a direction away from the dimple (positive pitch static attitude), whereas the traces try to hold them back as they are not plastically deformed. As a result, the final rotation of the flexure tongue, which in turn provides the pitch static attitude, is less than what would have been achieved if the traces were not present. The traces also stay out of the plane of the flexure legs, and bowed as shown in  FIG. 5 . The existence of stress in the traces, its release and effect on pitch static attitude can easily be verified by cutting the traces. When the traces are cut, the stress is released, the tongue moves to the appropriate position dictated by the deformation of flexure legs without the hold back from traces. As a result the pitch static attitude is increased. 
     The stress in the traces can also be partially or fully relieved when the integrated lead suspension or head gimbal assembly built thereof is subjected to thermal exposures. In such cases the pitch static attitude will increase to different degrees. One such case is when the slider and integrated lead suspension are electrically connected by a process called solder ball bonding (assignee&#39;s U.S. Pat. No. 5,828,031). The pads  185  are connected to the slider bond pads, by placing and reflowing discrete solder balls. The heat applied to melt the solder balls flows thru the traces, and softens the thermo plastic polyimide layer under the traces. Such softening in the areas  183 ,  184  relieves the stress on the traces from flexure leg forming and increases the pitch static attitude. A similar effect can also be observed if the integrated lead suspension, or the head gimbal assembly is subject to any thermal exposures in the process. 
     In one embodiment of the current invention, the stresses in the traces are eliminated at the source, that is during the flexure leg forming to attain the desired pitch static attitude (PSA)  145 . This can be achieved by simultaneous plastic deformation (such as with rollers or other mechanical devices  199  in  FIG. 7 ) of the flexure legs  165  as well as the outrigger lead traces  173  as shown in area  179   a  of  FIG. 4 . 
     There are several parameters that measure the performance of the slider  129 . Fly height  141  ( FIG. 5 ) is the separation between a point on the ABS  140  of the slider  129  and the surface of disk  115 , such as the center of the trailing edge  143  of the ABS  140  and the surface of disk  115 . Pitch is the tilting of the flying slider  129  in the longitudinal direction (see longitudinal axis  151  and lateral axis  153  in  FIG. 6 ) with respect to the plane of disk  115 . Roll (not illustrated) is the tilting of the flying slider  129  in the lateral or transverse direction with respect to the plane of the disk  115 . Fly height, pitch, and roll are all dependent on parameters like ambient pressure, temperature, air viscosity, linear velocity (product of radius from center of the disk and disk angular velocity or rpm), skew angle (angle between the longitudinal axis of the slider and the tangent to the current radius from the center of the disk), pre-load (the force applied by, for example, integrated lead suspension  127 ), integrated lead suspension moments (moments applied in the pitch and roll directions by integrated lead suspension  127 ), slider flatness, and the design of the slider air bearing  140  itself. The design of the slider  129  targets a low velocity and low skew dependent, fly height profile that remains substantially flat across the radius of the disk  115 . The spacing between the head  142  and the disk  115  is described by fly height, together with its pitch and roll. 
     The performance of a slider head also may be measured in terms of sensitivities. The sensitivities of the slider  129  describe its change in fly height, pitch, or roll when another parameter that affects the fly height changes by one unit. For example, “sensitivity to pre-load” measures the decrease in fly height when the pre-load force is increased by one gram. “Sensitivity to slider flatness” is another parameter. The various surfaces of the slider air bearing are not perfectly flat since the slider  129  exhibits a longitudinal curvature or crown, a transverse curvature or camber, and a cross curvature or twist. Among these features, crown has a significant effect on fly height. 
     In general, the parameters that affect fly height are associated with the integrated lead suspension  127  (pre-load, location of the dimple  144  with respect to the slider  129 , static attitudes in the pitch and roll directions), slider  129  (flatness and size of ABS, etch depths, mask alignment, and rail width), and operating conditions (ambient temperature, pressure, viscosity, and velocity). It is desirable for slider  129  to have low sensitivities since that implies that the departure of fly height from its desired target is small. Each parameter affecting fly height is described statistically by its mean and standard deviation. A tight distribution of values for a parameter around their mean implies that the spread or standard deviation is small. 
     For example, “fly height sigma” is a statistical estimator of the fly height variation of a group of sliders. This parameter is proportional to the standard deviation of other parameters that affect fly height, and to the sensitivities of the design of air bearing. Thus, by designing a slider to possess low sensitivities, and by ensuring that the manufacturing process is very repeatable, a tight distribution of fly heights is realized. 
     There are also a number of specific requirements for the head and slider that should be met. Since disks are not perfectly flat and exhibits waviness or curvature that affects fly height, it is desirable that sliders respond consistently to changes in the curvature of the disks. There are at least two disk curvatures of interest. One is in the tangential direction is related to the crown of the slider. Another is in the radial direction and is related to the camber of the slider. Because of the magnitude of the radial curvature near the rim of the disk (also called roll-off or ski jump), it is important for sliders to feature a low transverse curvature sensitivity. The flatness sensitivity of sliders is significant in this respect. 
     Another requirement for sliders is low fly height and roll sigmas. The variability in fly height of sliders must be consistent. In particular, the roll standard deviation must be small since it is the spacing between the trailing edge  143  ( FIG. 5 ) of head  142  and disk  115  that controls the fly height. If the trailing edge  143  is perfectly parallel to the disk  115 , the clearance is uniform. Any amount of roll creates an uneven clearance in the lateral direction between the head  142  and the disk  115 . 
     As a related requirement, sliders should have good load/unload performance. During operation, a slider  129  is loaded onto a spinning disk  115  and must establish its supportive air bearing to avoid contact with the disk  115 . Ideally, there will be no exposure to contact during the load/unload sequences. However, physical contact with the disk  115  is almost inevitable and can be a disturbing event on the fly height  141  as it causes the head  142  and slider  129  to lose support and cause damage to the disk  115 . 
     The static attitude of the slider maintains the angular position of the slider with respect to the mounting platform and is specified by design in conjunction with a specific ABS. In this way, the slider can maintain an optimal flying height for the transducer thereon to read and/or write data on to the recording surface of the disk. To counter the airlift pressure exerted on the slider during disk drive operation, a pre-determined load is applied through a load point on the suspension to a precise load point on the slider. The slider flies above the disk at a height established by the equilibrium of the load on the load point and the lift force of the air bearing. The load of the suspension, together with static attitude, control and maintain the optimal flying height of the slider. 
     The pitch static attitude in a suspension is produced to a desired value by forming the flexure legs, and then making adjustments by mechanical and/or thermal methods during the manufacturing of the suspension. The traces are joined to the flexure legs near the transducer bonding area in front of the slider, and also near the back (i.e., the leading edge) of the slider. Since the traces are an integral part of the flexure in an integrated lead suspension, the traces provide resistance to the deformation of the flexure leg and the deflection of the flexure tongue by an opposing force. Hence, a significantly higher force is needed to plastically deform the flexure legs to obtain a desired pitch angle, which also includes the overcoming the opposite forces produced by the traces. This process leaves residual stresses in the traces, which cause the traces to move out-of-plane with the rest of the flexure. One way to confirm the existence of stress in the traces is to cut the traces or subject the suspension to thermal processes. The residual stresses in the traces are relieved by either process and, as a result, the slider pitch angle is increased. 
     The presence of residual stresses in the traces is an inherent problem of the integrated lead suspension. Once the suspension is manufactured by the supplier with formed flexure legs and adjustment to achieve a desired pitch angle, it comes with a variable amount of stress in the conductive traces. A part or all of the stress is likely to be relieved if and when the suspension is subjected to a thermal process, thereby changing the pitch static attitude of the suspension or head gimbal assembly. 
     In one embodiment, the flexure  163  is formed from stainless steel. A set of flexure legs  165  form a portion of the flexure  163  and define an aperture  167  near the distal end of the flexure  163 . A tongue  169  extends into the aperture  167  from the flexure legs  165  for providing a mechanical support structure to which the slider  129  is bonded. The flexure legs  165  are spaced apart from the longitudinal axis  151  at a lateral, flexure leg distance  171  that is measured between the longitudinal axis  151  and the flexure legs  165 . The flexure leg distance  171  need not be identical for each flexure leg  165 . 
     Integrated lead suspension  127  also comprises a set of outrigger leads  173  that are mounted to the flexure  163  for carrying electrical signals. In one embodiment, the outrigger leads  173  are formed from copper and are electrically insulated from flexure  163  by insulating layer  175 . Insulation  175  may comprise, for example, a dielectric (such as polyimide) that itself is formed from, e.g., three layers of materials. Insulation  175  has as an inert core layer of Kapton® that is covered on each side by another material, such as a thermoplastic polyimide, that bonds to the copper leads  173  and the steel of flexure  163 . As shown in  FIG. 6 , the copper outrigger leads  173  “exit” from the end of stainless steel flexure  163  beyond slider  129  approximately at the areas  172 , such that outrigger leads  173  are “outboard” of flexure  163 , as will be described below. 
     In the embodiment shown, the outrigger leads  173  are located on each lateral side  180  of the flexure  163  such that there are outrigger leads  173  located laterally outboard of each of the flexure legs  165 . In this version, there are two outrigger leads  173  on each side  180  of the integrated lead suspension  127 . Each of the outrigger leads  173  is laterally spaced apart from the longitudinal axis  151  at an outrigger distance  177  that is greater than the flexure leg distance  171 . The various individual outrigger leads  173  typically have different outrigger distances  177 , but each of the outrigger legs  173  is completely laterally outboard of the flexure legs  165 . 
     The slider  129  mounted to the tongue  169  of the flexure  163  such that electrical contact is established between the slider  129  and the outrigger leads  173 . The slider  129  is electrically interconnected with the outrigger leads  173  by solder ball bonding, which requires significantly high temperatures (approximately 200+ degrees C.) to reflow the solder balls  170  ( FIG. 5 ). Such relatively high temperatures during the head gimbal assembly process causes the pitch static attitude  145  of the slider  129  to go out of control in the prior art as the excess heat from solder ball bonding flows through the conductors of outrigger leads  173 . Solder ball bonding thermally affects the residual stress level in the outrigger leads  173  and, thus, affects the pitch static attitude  145  of the slider  129 . The outrigger leads  173  have residual stress due to the techniques used to form them in the prior art. 
     A similar effect can also be observed if the integrated lead suspension, or the head gimbal assembly is subject to any elevated temperature thermal exposures. 
     As described above for  FIG. 7 , all of both the flexure legs  165  and the outrigger leads  173  are simultaneously plastically deformed during the manufacturing of the integrated lead suspension to permanently define a pitch static attitude angle  145  of the slider  129 . In one embodiment, the flexure legs  165  and the outrigger leads  173  are plastically deformed at approximately a same longitudinal location  179  along the longitudinal axis  151 . 
     In operation, the present invention also comprises a method of setting the pitch static attitude  145  for the slider  129  on the integrated lead suspension  127 . The method comprises providing an integrated lead suspension  127  having a longitudinal axis  151 , a lateral axis  153  transverse to the longitudinal axis  151 , a load beam  161 , a mount plate  162 , a flexure  163  having flexure legs  165  and a tongue  169  for providing a mechanical support structure, and outrigger leads  173  for carrying electrical signals. The method further comprises configuring the integrated lead suspension  127  such that each of the outrigger leads  173  is laterally spaced apart from the longitudinal axis  151  at an outrigger distance  177  that is greater than a flexure leg distance  171  between the longitudinal axis  151  and the flexure legs  165 , thereby defining said each of the outrigger legs  173  as being completely laterally outboard of the flexure legs  165 . Again, the individual distances  171 ,  177  are not necessarily required to be identical for each flexure leg  165  and outrigger lead  173 , respectively. The method may comprise locating the outrigger leads  173  on each lateral side of the flexure  163  such that there are outrigger leads  173  located outboard of each of the flexure legs  165 . 
     The slider  129  is mounted to the tongue  169  of the flexure  163 , and electrical contact is established between the slider  129  and the outrigger leads  173  through a heating process that incidentally alters the residual stresses in the outrigger leads  173  and changes the pitch static attitude  145  of the slider  129 . This method is ideally designed for integrated lead suspensions (ILS) rather than circuit integrated suspensions (CIS), and preferably includes solder ball bonding the slider  129  to the outrigger leads  173 . Prior art ILS joining techniques used gold ball bonding (GBB) to electrically interconnect the leads and slider. Gold ball bonding occurs at relatively low temperatures, such as room temperature, which do not thermally affect the residual stress level in the leads and, thus, do not affect the pitch static attitude of the slider. 
     The next step of the method of the present invention includes simultaneously plastically deforming both the flexure legs  165  and the outrigger leads  173  during the manufacturing of the integrated lead suspension to produce a stable pitch static attitude  145  of the slider  129 . As shown in  FIG. 7 , the deforming step may comprise, for example, simultaneously creasing both the flexure legs  165  and the outrigger leads  173  with a roller, or simultaneously step-forming both the flexure legs  165  and the outrigger leads  173 . Moreover, this step may comprise simultaneously plastically deforming all of both the flexure legs  165  and the outrigger leads  173  at approximately the same longitudinal location  179  ( FIG. 6 ) along the longitudinal axis  151 . In addition, the method may further comprise protecting the outrigger leads  173  from mechanical damage, such as scratching, during the plastic deformation. The prior art cannot satisfy the present invention&#39;s step of deforming (incidentally or otherwise) the outrigger leads  173  by relieving stress in the outrigger leads  173  with heat from the heating process. 
     The present invention has several advantages and is ideally suited for providing an improved hard disk drive. The slider of the integrated lead suspension is electrically interconnected with the outrigger leads on the suspension by solder ball bonding. Solder ball bonding requires significantly high temperatures to reflow the solder balls. When such temperatures are applied to the suspension during the manufacturing process, the pitch static attitude of the slider can go out of control as the excess heat from solder ball bonding flows through the conductors of outrigger leads. Solder ball bonding thereby thermally affects the residual stress level in the outrigger leads and, thus, affects the pitch static attitude of the slider. 
     This problem is overcome by simultaneously plastically deforming both the flexure legs and the outrigger leads during the manufacturing of the integrated lead suspension. The process eliminates any stress on the traces and produces a stable pitch static attitude that is not affected by subsequent thermal processes. The flexure legs and the outrigger leads are deformed at approximately the same longitudinal location. The deformation simultaneously creases both the flexure legs and the outrigger leads with a roller, or simultaneous step-form both the flexure legs and the outrigger leads. 
     While the invention has been shown or described in only some of its forms, it should be apparent to those skilled in the art that it is not so limited, but is susceptible to various changes without departing from the scope of the invention.