BSOB模式与BBOS模式

1、ASM CHAPTER 6 ASM Bond Stick On Ball(BSOB)/Bond Ball On Stitch(BBOS)/ Tail Break ASM 1.0) BOND STICK ON BALL(BSOB) 1.1) Description This bonding process is specially developed by ASM to handle multi-die(MCM) bonding application. In the conventional approach, if one is trying to connect the gold wire

2、 from one die to the another, a capillary mark of second bond will be evident on top of the die which may damage the die. The BSOB process will solve this problem by bonding a ball onto the dies surface first, followed by bonding another wire where the second bonds wedge will be landing on top of th

3、is bonded ball(figure 1). ASM Die 1Die 2 Bond Ball 2nd Bond(wedge) 1st Bond Figure 1 : Bond Stick On Ball(BSOB) ASM 2.0) BOND BALL ON STITCH(BBOS)/ SECURITY BOND 2.1) Description This process is also known as security bond. It bonds a ball on top of the wedge of the normal connection wire.This proce

4、ss is mainly used to secure the second bond sticking capability.(Figure 2) Die 1 Lead Bond Ball 2nd Bond (wedge) 1st Bond Figure 2 : Bond Ball On Stitch (BBOS) ASM 3.1) Free Air Ball (FAB 2)is aligned to the center of the bond pad on device 2. Device 1Device 2 FAB 2 3.0 STANDOFF BALL CONTROL BONDING

5、 SEQUENCE ASM 3.2) Capillary descends and bonds ball to bond pad. Device 1Device 2 W/clamp open Capillary Application of 1st bond stand off ball parameter to form Ball Thickness and Ball Size During Stand Off Bonding , SOB parameters are applied . ASM 3.3) Capillary rises to loop base to clear ball.

6、 Device 1Device 2 W/clamp open Capillary rises to set Loop Base Loop Base Contact Pt. Loop base is the distance between the capillary tip and contact point. Recommended setting = 2 ASM 3.4) Capillary move to programme ball offset. Ball offset can be programmed towards or away from the first bond. +

7、ve towards 2nd bond - ve away 2nd bond Device 1Device 2 W/clamp open Actual Ball Offset = Setting x 10um If Ball Offset Setting = 22 Then Actual Loop Base =220um Recommended Setting = - ve 35 ASM 3.5) Capillary descends and forms stitch bond on top of the ball. Device 1 Device 2 W/clamp open *Ball T

8、hickness SOB Parameter (Stand Off Ball Parameter) Capillary descends to set Ball Thickness (Amt. Z movement above the ball height) Contact Pt. * Ball Thickness is the distance between the capillary tip and contact point Recommended setting = 2 ASM 3.6) Capillary moves horizontally for a scrub distan

9、ce to weaken the wire at ball neck. Device 1Device 2 W/clamp open Scrub one direction away from ball Actual Scrub Distance = Setting x 0.8 um If Scrub Distance Setting = 10 Then Actual Scrub Distance = 8 um Capillary move to set Scrub Distance One direction ONLY - Away from the ball Recommended sett

10、ing = 8 ASM 3.7) Capillary rises to tail height Device 1Device 2 W/clamp close Capillary moves to set Tail Length (Amount Z movement above the bump before the wire clamp closes) Recommended setting = 35 ASM 3.8) Capillary rises and tears the wire, as BH ascend to Fire Level. Device 1Device 2 W/c clo

11、se ASM 3.9) EFO fires to form free air ball. Cycle repeats until all “Standoff Ball” are placed. Device 1Device 2 Bond Ball FAB ASM 3.10) After placing all standoff balls. The machine continue to bond wires. 2nd Bond(wedge) 1st Bond Device1Device2Device1 Bond Ball ASM Bump ball formation for BSOB/BB

12、OS MOTION BO LB BT SC Normal LB BO BT Scrub Flat LB BO BT Scrub=0 CONE LB BO BT=LB Scrub=0 LB BO BT LB BO The bump ball formation process is almost like bonding a normal wire, including 1st bond, looping and 2nd bond parameters. ASM 4.0) PARAMETER DEFINITION IN STAND OFF BALL CONTROL MENU 4.1) Loop

13、Base This parameter determines the loop level of the bondhead which should be sufficient to avoid the ball. Range: Loop Base 0 5 Setting : 2 4.2) Ball Offset This setting controls the distance of the table move in order to offset the capillary from the standoff ball. Negative value can be moved towa

14、rds to the first bond. Positive value can be moved away from the first bond. Range: Ball Offset - 40 20 Setting : - ve 35 ASM 4.4) Scrub Distance This setting controls the capillary moves horizontally with a Scrub amplitude to weaken the wire at neck. It is always away from the first bond. Range: Sc

15、rub Dist 4 12 Setting : 8 4.5) Tail Length This setting controls the length of the tail where the bondhead rises to the preset height before the wire clamp is closed. Range : Tail Length 30 40 Setting : 35 4.3) Ball Thickness This parameter refer to the ball thickness which controls the level of the

16、 bondhead as it descends to the top of the ball Range: Ball Thickness 0 5 Setting : 2 ASM 4.6) Time Base 1/2 This setting controls the bond time applied to the standoff ball control only. Time 1 for the 1st bond and Time 2 for the 2nd bond. 4.7) Power Base 1/2 This setting controls the ultrasonic po

17、wer applied to the standoff ball control only. Power 1 for the 1st bond and Time 2 for the 2nd bond. 4.8) Force Base 1/2 This setting controls the bonding force applied to the standoff ball control only. Force 1 for the 1st bond and Force 2 for the 2nd bond. ASM 4.9) Standby Power 1/2 This setting c

18、ontrols the power activated when the bonding head reach the search level, to the moment the bond head contacts the bond surface. With the vibration, before contact take place. Bond head will clean up the pad surface and remove water vapor on the pad. This parameter used for the standoff ball control

19、 only. 4.10) Contact Time 1/2 Refer to the Contact time 1/2 definition in Bond Parameter menu. But this parameter will be affected on the Standoff ball control only. ASM 4.11) Contact Power 1/2 Refer to the Contact Power 1/2 definition in Bond Parameter menu. But this parameter will be affected on t

20、he Standoff ball control only. 4.12) Contact Force 1/2 Refer to the Contact Force 1/2 definition in Bond Parameter menu. But this parameter will be affected on the Standoff ball control only. ASM Figure 4 : Standoff Ball Control Parameter Display(page 2) 5.0 BSOB WIRE PARAMETERS ASM 5.1) Wire Offset

21、 In -Menu This is the offset parameter that is required to ensure maximum contact area between the stitch bond and ball. It is always away from the first bond. Range: Wire Offset 10 30 Recommended setting = 25 5.2) Second Bond Search Speed This Parameter controls the impact for stitch on ball. Range

22、: Search Speed 2 32 256 Recommended setting = 32 2nd Bond Wedge Stand Off Ball Capillary position during stitch bond ASM 5.3) Time Base 1/2 This setting controls the bond time applied to the device. Time 1 for the 1st bond and Time 2 for the 2nd bond. 5.4) Power Base 1/2 This setting controls the ultrasonic power applied to the device. Power 1 for the 1st bond and Time 2 for the 2nd bond. 5.5) Force Base 1/2 This setting controls the bonding force applied to the device. Force 1 for