JP3475802B2 - Electronic component bonding equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an apparatus for bonding electronic components which can prevent the temperature of a bonding tool from increasing and suppress the change of vibration characteristics. SOLUTION: An apparatus which bonds electronic components by imparting vibration to them while pressing an electronic component 30 against a substrate 30, which is heated and held by a substrate holding table 33, is provided with a covering member 41 which shields a horn 20b and a vibrator 21 of a bonding tool 20 from the radiant heat from the substrate holding table 33 by covering them. Furthermore, air is supplied into the covering member 41 to cool the born 20b and the vibrator 21. This allows for the change in vibrational characteristics due to increasing temperature of the vibrator 21 to be suppressed and the vibration transferred to the electronic component 30 to be prevented from damping to stabilize the quality of bonding.

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic component joining apparatus for joining an electronic component to a substrate. 2. Description of the Related Art As a method of joining an electronic component to a substrate,
A method using ultrasonic pressure welding is known. In this method, ultrasonic vibration is applied while pressing an electronic component against a substrate by a bonding tool, and the bonding surfaces are rubbed against each other for bonding. In this method, as a bonding tool, a tool in which a vibrator that is a source of ultrasonic vibration is attached to an end of a horn provided with a bonding action portion that contacts and presses an electronic component is used. As the vibrator, a piezoelectric element that converts electric vibration into mechanical vibration is often used. [0003] The characteristics of a piezoelectric element used in a vibrator have temperature dependence, and when the temperature rises above a certain temperature, characteristics such as the frequency change. However, a holding table for holding a substrate to which electronic components are bonded is often provided with a heater for heating the substrate. In such a case, a bonding tool or a vibrator requires time due to radiant heat from the holding table. The temperature rises over time. As a result, the vibration characteristics change and a difference from the initially set vibration condition occurs, so that the optimum vibration as set is not transmitted to the bonding tool, which adversely affects the bonding quality and efficiency of the ultrasonic pressure welding. was there. Accordingly, an object of the present invention is to provide an electronic component bonding apparatus capable of preventing a temperature rise of a bonding tool and suppressing a change in vibration characteristics. [0005] An electronic component bonding apparatus according to the present invention comprises a substrate holding table for holding and heating a substrate, an elevating member that moves up and down above the substrate holding table, and a lower part of the elevating member. A horn mounted in a horizontal position and vibrated by a vibrator, and a joining action portion that projects downward from the horn, contacts the electronic component and presses the electronic component against the substrate, and transmits vibration of the horn to the electronic component. and cooling means for cooling the vibrator, provided with a heat insulating means for interrupting heat transfer from the substrate holding table to the horn and or vibrators, the bonding working portion is the heat insulating hand
Protruding downward from the opening provided at the center of the step
And the cooling means supplies air inside the heat insulating means.
Supply . According to the present invention, by providing a heat insulating means for interrupting heat transfer to the horn and / or the vibrator of the bonding tool and a cooling means for cooling the vibrator, a change in the characteristics of the vibrator is suppressed and the bonding quality is reduced. Can be stabilized. Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a front view of an electronic component bonding apparatus according to an embodiment of the present invention, and FIG. 2 is a front view of a bonding head of the electronic component bonding apparatus. First, the structure of the electronic component bonding apparatus will be described with reference to FIG. On the front surface of the support frame 1, a first elevating plate 2 and a second elevating plate 3 are provided so as to be able to move up and down. A cylinder 4 is mounted on the first lifting plate 2, and its rod is connected to the second lifting plate 3. A bonding head 10 is mounted on a second lifting plate 3 which is a lifting member.
A Z-axis motor 6 is provided on the upper surface of the support frame 1, and the Z-axis motor 6 rotates a vertical feed screw 7. The feed screw 7 is screwed into a nut 8 provided on the back surface of the first lifting plate 2. Therefore, when the Z-axis motor 6 is driven, the first lifting plate 2 and the second lifting plate 3 move up and down. In FIG. 1, a substrate 32 is held on a substrate holding table 33, and the substrate holding table 33 is placed on a movable table 34. By driving the movable table 34, the substrate 32 moves in the horizontal direction and is positioned below the bonding head 10. Substrate holding table 33
Is provided with a heater 40 for heating the substrate 32. The main control section 35 controls the Z-axis motor 6 via a motor drive section 36 and controls the movable table 34 via a table control section 37. The cylinder 4 is connected to the main controller 35 via a load controller 38,
The protrusion output of the rod 5 of the cylinder 4, that is, the pressing load for pressing the electronic component 30 against the substrate by the bonding tool 20 is controlled. A holder 12 is attached to a lower end of a main body 11 of the bonding head 10, and a bonding tool 20 is attached to the holder 12. A vibrator 21 is mounted on an end of the bonding tool 20. Hereinafter, the bonding tool 20 will be described with reference to FIG. In FIG. 2, on the lower surface of the holder 12,
The bonding tool 20 is horizontally fixed via a fixing member 20a. Bonding tool 20 is vibrator 2
1 and a horn 20b vibrated by the vibrator 21
And the joining action portion 20c protruding downward from the horn 20b
It has. The joining action portion 20c contacts the electronic component 30 and presses the electronic component 30 against the substrate 32, and transmits vibration of the horn 20b to the electronic component 30. A cover member 41 is attached to the lower surface of the holder 12. The cover member 41 protrudes below the bonding tool 20 including the vibrator 21, and only the bonding action portion 20 c protrudes downward from an opening 41 a provided at the center of the cover member 41. The cover member 41 blocks transmission of radiant heat from the substrate holding unit 33 heated by the heater 40 to the vibrator 21 and the bonding tool 20. That is, the cover member 4
1 is a heat insulating means. An air pipe 42 is guided above the cover member 41, and the air pipe 42 is connected to an air source 43. By supplying air around the bonding tool 20 and the vibrator 21 inside the cover member 41 through the air pipe 42, the vibrator 21
The bonding tool 20 is air-cooled. Therefore,
The air source 43 and the air pipe 42 are air cooling means for cooling the vibrator 21. This electronic component bonding apparatus is configured as described above, and its operation will be described below. In FIG. 1, an electronic component 30 is attached to a joining action portion 20 c of the bonding tool 20.
Is held, the Z-axis motor 6 is driven to lower the bonding tool 20. Then, the electronic component 30 is pressed against the substrate 32 and the vibrator 21 is driven to drive the electronic component 3 through the horn 20 b of the bonding tool 20.
By applying vibration to the electronic component 30,
2 is bonded. In this bonding process, the substrate holding table 33 is heated by the heater 40 to increase the temperature, and the radiant heat from the upper surface of the substrate holding table 33 is radiated upward. Since this radiant heat is blocked by the cover member 41, it is possible to effectively suppress the radiant heat from being directly transmitted to the bonding tool 20 and the vibrator 21. For this reason, the temperature of the vibrator 21 rises, the vibration characteristics change, and the vibration transmitted to the electronic component 30 is attenuated outside the vibration conditions initially set according to the shape and dimensions of the bonding tool 20. No deterioration of the joining quality due to the occurrence. Also, the bonding head 20 does not thermally expand due to a rise in temperature, and the vibration transmission efficiency does not decrease due to a delicate change in the position of the fixing member 20a for fixing the horn 20b. Furthermore, by supplying air to the inside of the cover member 41, an effective cooling effect can be obtained, and stable joining quality can be ensured. According to the present invention, since the heat insulating means for interrupting heat transfer to the horn and / or the vibrator of the bonding tool and the cooling means for cooling the vibrator are provided, the temperature of the vibrator can be increased. A change in vibration characteristics can be suppressed, and a reduction in vibration transmitted to the electronic component can be prevented to stabilize bonding quality.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a front view of an electronic component bonding apparatus according to one embodiment of the present invention. FIG. 2 is a front view of a bonding head of the electronic component bonding apparatus according to one embodiment of the present invention. 3 Second lifting plate 20 Bonding tool 20b Horn 20c Bonding section 21 Vibrator 30 Electronic component 33 Substrate holding table 41 Cover member 42 Air pipe 43 Air source

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-10-22308 (JP, A) JP-A-7-115109 (JP, A) JP-A-7-221141 (JP, A) JP-A-60-1985 194534 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H01L 21/60 311 H01L 21/52

Claims (1)

(57) [Claim 1] A substrate holding table for holding and heating a substrate, an elevating member that moves up and down above the substrate holding table, and is mounted below the elevating member in a horizontal posture. A horn vibrated by the vibrator, a bonding portion for projecting downward from the horn, abutting against the electronic component to press the electronic component against the substrate, and transmitting vibration of the horn to the electronic component, and cooling the vibrator cooling means comprises a heat insulating means for interrupting heat transfer from the substrate holding table to the horn and or vibrators, the bonding working portion is the cross-sectional
Protruding downward from the opening provided in the center of the heating means
And the cooling means has air inside the heat insulating means.
An electronic component joining apparatus, characterized by supplying: